If you look at several sets of Individual Defensive Player (IDP) rankings compiled by fantasy "experts," one of the first things that leaps out at you is the significant variation from one list to the next, much more so than you'll usually find in rankings for offensive players. This can reflect differences in the scoring used as a default in generating the rankings (which hammers home the all-important IDP draft rule of knowing the scoring in your league and how it affects player values), a difference in philosophy from ranker to ranker, or even the personal preferences or biases of a particular ranker. For example, I hate Quintin Mikell, as he has been conspiring to destroy my IDP teams since I started playing in this format. I'm on to you Quintin, and you will not succeed. Rankings also change a great deal as they're updated and injuries, depth chart changes, and schematic changes or tweaks wreak havoc on individual defensive player values. Nowhere was this more evident than in this truncated NFL offseason, as the rankings that were cranked out before the lockout ended have been eviscerated by the innumerable player moves that have occurred since the NFL light bulb finally came on. With the help of FantasySharks' resident IDP mastermind, the honored and esteemed James Elvins (figured it might be nice to involve one person who had an idea what he was talking about), let's take a deeper look at a few players whose IDP values seem to be up for debate, whether it's due to a change in role, health or just the fact that fantasy football pundits can be a contrary bunch. With that, let's start the IDP Showdown! Paul Posluszny, LB, Jacksonville James Elvins: You know what, I'm actually liking Posluszny to challenge for No. 2 overall IDP this year (Carolina's Jon Beason at No. 1 for me -- that defensive line is gosh awful. I know some people don't like him for moving away from the Buffalo Bills value wise, but I don't think his value is affected in this change. I think it's improved as you have two franchises at different stages of their rebuilding. Buffalo have been consistently working on their defensive line for the past three years. Look at their draft picks. Jacksonville has only just come into the light in that respect. They will be starting two rookie defensive tackles. Their big offseason free eagent acquisition on the line (Ron Edwards from Kansas City) has already gone on Injured Reserve. Their former first-round defensive end (Derrick Harvey) has been cut and they have an oft-injured lineman as one of their premier pass-rushers (Aaron Kampman). Honestly, that's a pretty mediocre line at best, which makes for pretty good IDP production not just for Posluszny, but for everyone that will have to pick up the pieces behind it. I look at Buffalo with Marcell Dareus, Kyle Williams and Dwan Edwards, with players like Torrell Troup, Alex Carrington and man-mountain Michael Jasper behind them and I'm thinking, "You know what? That line has the makings of being a good solid foundation moving forward." I look at Jacksonville and I don't see that at all. Terrance Knighton is badly overweight and out of shape, but can play to a decent standard. Tyson Alualu played hurt for much of last season so it's hard to know what to expect out of him this year. I like the kid, but he's shouldering a lot of responsibility. Kampman could go down at any time at all on the end and Matt Roth is coming off a season at outside linebacker in Cleveland. It's a line that can go any which way (but likely down) with an offense that will do similarly courtesy of David Garrard and Blaine Gabbert, which will put their guys back on the field. Anyone downgrading Poz because of the move hasn't accounted for the improvement in Buffalo and regression in Jacksonville. It's "status quo" in terms of his value - no move, no change. Jacksonville ranked 22nd in run defense last year, Buffalo 31st. I see them switching places this year and Posluszny owners should be deliriously happy, provided he can stay healthy again. With 151 tackles in 14 games last season and an 8.8 tackle per game career average, you might be happy enough either way. Gary Davenport: I'm going to have to disagree with Mr. Elvins on this one, as I believe there are a number of reasons to believe that Posluszny might be in for a dip in IDP production in 2011. First, the Bills' defense faced a well-above average number of tackle opportunities in 2011, and while I agree that the Jaguars' defense isn't going to make anyone soil themselves I'd expect the tackle opportunities Pozluszny sees to decrease this season. Second, Buffalo's scorekeepers awarded assists on a ridiculous 32 percent of plays a year ago, while Jacksonville's stat crew wasn't nearly as generous, making a drop in Posluszny's assist numbers (he had 48 in 2010) probable. Finally, the linebackers surrounding Posluszny in Buffalo weren't as talented as the corps he joins in Jacksonville, and I expect the likes of Daryl Smith and Clint Session to generate considerably more competition for tackles than his teammates with the Bills did. This is not to say that I'm "down" on Posluszny's IDP prospects for 2011, as I still expect him to finish safely in LB1 territory, but I think that fantasy owners that draft Posluszny looking for a repeat of his 150-plus tackle 2010 campaign are apt to end up disappointed, and he's dropped to near the bottom of my Top 10 fantasy linebackers for 2011. Osi Umenyiora, DE , New York Giants GD: No player has had a more Lifetime Movie Network offseason than Umenyiora, who began training camp in a nasty contract tiff with the Giants, then finally acquiesced and began practicing just in time to undergo knee surgery that will sideline him for anywhere from 3-6 weeks and could cost him a regular season game or two. Jason Pierre-Paul, who will start in Umenyiora's stead, has shown the ability to be a rock-solid defensive end in his own right, and it's conceivable (although somewhat unlikely) that if he plays lights-out football he could supplant Umenyiora in the starting lineup or at least force more of a rotation between the two. I've seen Umenyiora listed as anywhere from a mid-range IDP DL1 (apparently based off his strong resume, which includes two Top 3 IDP finishes at his position over the past three seasons) to a DL3 (based off durability concerns and the fear that Pierre-Paul will pass him on the depth chart), but for me the truth lies somewhere in between. I wouldn't want to count on Umenyiora as my IDP DL1, but if he slips in late IDP drafts he could represent an enticing risk/reward pick as your DL2. JE: Much like Tyvon Branch (see below), I'm open to parting company with him moving into 2012. Unlike Branch, his value in 2011 is greater to you if you own him than to absolutely anyone else. So you'll have to live with him if you've got him. This year's production? Between his knee and Pierre-Paul I'm thinking it's actually the veteran (Umenyiora) that will be the rotational guy on the line rather than the sophomore (Pierre-Paul), just to help keep his knee healthy. You can see why he was angling for a big contract and you can also see why the Giants were loathed to issue one. Tier 2 defensive end production for me. In redraft leagues I'm targeting Pierre-Paul over him. Let's face it -- if Umenyiora was on any line other than the Giants (with perhaps the exception of the Detroit Lions) he'd be going in the mid-to-late rounds. Jerod Mayo, LB , New England JE: Quite simply, he stays top tier. You've heard it, I've heard it. Positional changes and scheme changes. I trust Bill Belichick about as far as I can throw him, but here are his thoughts on Mayo. "Yeah, I mean, I don't really see that. Maybe the next coach can put him there, I don't know. But I think he's going to play off the line of scrimmage and he's going to play in the tackle box somewhere." "Whatever front we're in -- over, under, 3-4, 4-3, 2-4 -- I mean, he's going to play in the tackle box (and) off the line of scrimmage; that's what he's always done. He's one of the best I've coached, one of the best in the league at (playing inside). I can't imagine him playing anywhere else, at this point." We've seen WILL linebackers (the weak side linebacker or guy to the right of the middle linebacker in a 4-3 defense) put up better numbers than the MIKE (middle linebacker) before. Ask Chad Greenway or Daryl Smith. Mayo will still be the linebacker to own. This news has more to do with Brandon Spikes than Mayo. Spikes showed up huge this offseason and has shown a rapid maturity and progression in his skills to become the next big linebacker from the University of Miami -- Ray Lewis, Jon Beason, Daryl Smith, D.J.Williams, Rocky McIntosh. GD: Mayo was the top linebacker in fantasy football a year ago and led the NFL with 175 tackles, but there are ample reasons to believe a repeat as top linebacker is unlikely. First, any time you see a player with a large number of assisted tackles (Mayo had an eye-popping 64 in 2010), it raises concerns about the sustainability of those tackle numbers, even with a stat crew that's as generous as New England's in doling out assists. Second, and more importantly, the Patriots have featured a lot more 4-3 defensive looks in training camp and thus far in the preseason, with Mayo sliding over to WILL linebacker and Spikes playing at middle linebacker. This formation could free up Mayo for more big plays (the fourth-year pro had two sacks in New England's first preseason game), but big plays can also be fluky, and should Mayo find himself outside on a significant number of snaps you have to wonder how that will impact his tackle numbers, especially should Spikes join him in the nickel. I'm not saying it's Chicken Little time, and Mayo should at least remain a decent IDP LB1, but this new wrinkle from Belichick gives me enough pause to drop Mayo from my Top 5 at the position. Tyvon Branch, SS, Oakland GD: Defensive backs are volatile enough week to week, much less year to year, but Branch has been an exception to that rule, posting back-to-back Top 10 fantasy finishes at his position. That said, it's been a rollercoaster offseason for Branch owners, with concerns that Branch would move to free safety allayed by Oakland retaining Michael Huff followed by more concerns about Branch's IDP value after a recent report suggested that Branch would shift to free safety in nickel situations this year, with Huff moving into the slot corner role. Branch has been one of the more discussed IDPs at the FantasySharks message board (www.fantasysharks.com/forum/viewtopic.php?f=38&t=234852) of late, with some wondering whether this potential switch could spell doom for Branch's IDP value or mean absolutely nothing at all. The truth once again (as it usually does) probably lies somewhere in the middle, as while considerable snaps at free safety could cause a slight dip in tackle opportunities and IDP production the fact that Oakland has enough faith in his coverage skills to put him there could mean he's capable of covering the occasional tight end or slot receiver (and tackling them, or maybe even picking off a pass or two), leaving Branch safely within the realm of IDP DB1 and every-week fantasy starter. JE: First and foremost, I think some clarity needs to be established, while you would want to own the strong safety over the free safety 9-times-out-of-10, it doesn't mean that the free safety is fantasy useless. Chris Hope, Michael Huff and Kerry Rhodes both outperformed a significant number of strong safeties last year hovering around the Top 15 in safety production. IDP production can be linked to a number of factors. Defensive backs (and safety in particularly) are no different. You ever draft a kicker on a decent passing team, knowing that their running game would mean they'd struggle to break the plane when they got down to where it matters? Same story, different circumstances. For a strong safety you want as leaky a run defense as you can lay your hands on. One of the main functions of the strong safety is to act as a safety net for the linebackers against running backs. There are other functions they perform, but for the sole purpose of FF production that's all we're focusing on. The team ranked 26th against the run -- Washington -- Laron Landry (No. 1) scored 21.3 fantasy points per week. 27th -- Cleveland -- T.J. Ward (No. 3)/ 16.59 points per week 28th -- Tamp Bay -- safety by committee (injuries aplenty) 29th -- Oakland -- Branch (No. 10), Michael Huff (No. 14)/ 15.77 and 14.97 30th -- Arizona -- Kerry Rhodes (No. 6), Adrian Wilson (No. 19)/ 15.95 and 13.69 31st -- Denver -- Brian Dawkins (No. 21)/ 13.41 32nd -- Buffalo -- Donte Whitner (No. 2)/ 17.75 So, if a defense figures to either spend less time on the field (more efficient offense that can move down the field and run the ball effectively) or be more efficient in their run defense then tackle opportunities -- the bread and butter of the strong safety production -- diminish. Also, unlike a lot of other franchises the hierarchy in Oakland is far from settled. Yes, Branch appears to be at the top of the tree but is that settled moving forwards? How many startable safeties has Oakland got right now? Three, four? (Branch, Huff, Mitchell, Hiram, Brown). Being the best tackler on a 4-3 leaky run defense team is all well and good. Don't know if people have noticed, but times do change in the NFL. Ask Detroit or the New York Jets. Being the best tackler on a team that has a decent offense, isn't as leaky against the run, has competition for the starting job, being surrounded by other athletic freaks that can close the distance (three out of five of those safeties are sub 4.3 runners) and a potential position switch and more defensive back sets (4-2-5, 2-4-5) before you even discuss a potential franchise move in the future (Can Al Davis afford Branch with all those other safeties and being so close to the cap he couldn't keep Zach Miller?) is not quite so good. Is it? For whatever it's worth, I think the Raiders made a great offseason acquisition in grabbing Chuck Bresnahan. The guy is just hands-down a great defensive coordinator. Sure he's coming in from the UFL (where incidentally he held the league's leading rusher to under 55 yards and almost went three games without conceding a touchdown and kept the two best teams in the league to under 95 yards rushing combined. Yes, they are NFL rejects, but he's working with NFL rejects) but it's also the same guy that helped put the Raiders in reaching distance of a Super Bowl and three division titles (2000-03) as well as a Top 3 defense. It won't happen overnight - saying and doing aren't the same thing, which is why im relatively bullish on Branch, but it will happen. I'll leave the last word on the run-tackling opportunities with OAK HC Hue Jackson: "I've said it to our staff and I'll say it to our team, I am committed as long as I'm here that we will stop the run. That's a passion of mine ... What I'm saying is I'm not going to allow someone to take the ball and run it down our throats. I'm not going to be a part of that. That's how I feel about it and we're going to get that buck stopped." Branch was just inside the Top 10 for strong safeties last year. I'm sure he'll stay top tier this year and be very ownable in IDP redrafts, but my advice is to save yourself the headache moving into 2012. It's why Bernard Pollard went in the sixth round despite other safeties going ahead of him in the ongoing Wall IDP redraft. Uncertainty about his production. Competition. Franchise change. Dynasty is all about knowing when to sell and when to buy. My advice is sell, stash Mitchell or Brown and then grab someone like George Wilson instead and enjoy spending your third- or fourth-round pick or upgrade at linebacker, defensive end or whatever other position instead.