Over the first two lessons of the Fantasy Sharks Individual Defensive Player (IDP) Tutorial, we've covered "broad strokes" topics, such as knowing your scoring and some basic IDP draft strategies. With those broad strokes concepts under your belt, you can emerge from many IDP drafts with your dignity intact and a fairly competitive defensive squad.

Congratulations, you've graduated...from elementary school.

Now, it's time to delve a bit deeper, to get into more detail, to dig beneath the surface into the meat of IDP. It's time to kick things up a notch, and we're going to start that by taking a look at each of the three main IDP positions.

We're going to begin those positional breakdowns by taking a look at the big ‘uglies,' the men in the trenches, the bane of quarterbacks everywhere...the defensive linemen.

When preparing for your IDP league's draft, the word of the day where defensive linemen are concerned is scarcity. The number of consistent weekly starters and so-called "elite" fantasy options on the defensive front continues to dwindle with each passing year. That, in turn, increases the IDP value of these players, and makes having at least one dependable weekly fantasy starter on the defensive line a definite advantage, if not a necessity.

The primary reason for this is simple. Speaking in rather general terms, 4-3 defensive ends are the top dogs where IDP defensive linemen are concerned, but, as 3-4 and "hybrid" fronts increase in popularity in today's NFL, the number of those defensive ends is decreasing. Of the Top 20 IDP defensive linemen in Fantasy Sharks Default IDP Scoring in 2012, 16 (80 percent) were 4-3 defensive ends, compared to 63 percent (20-of-32) of NFL teams that ran the 4-3 defense, a number that will decrease even more in 2013.

So why is this? Why are the 4-3 ends preferable to their 3-4 counterparts? Well, once again we're speaking in rather general terms, but for many 3-4 teams the defensive line's job isn't so much to force the action as occupy blockers so that the linebackers behind them can wreak havoc. They don't exist to attack so much as hold the point of attack, and their statistical production suffers as a result.

There are, of course, exceptions. J.J. Watt, of the Houston Texans, was the top overall IDP last year. Calais Campbell, of the Arizona Cardinals, has been a Top 20 fantasy option in three of the past four seasons. However, those players are just that. They're exceptions, and defensive ends that play...

Vikings RE Jared Allen had the torn labrum in his left shoulder surgically repaired on Thursday.

Allen is expected to be ready for training camp. Playing hurt all season, Allen knew about the injury as far back as August but didn't disclose it to reporters until late in the year. Although the surgery will sideline him for most or all pre-training camp activities, Allen usually skips those anyway to train on his own. Allen finished the 2012 season with 45 tackles and 12 sacks.

Ah, the linebacker position. Despite the lofty numbers that J.J. Watt produced from the defensive end spot, linebackers are still the glamor boys of the Individual Defensive Player (IDP) format. They are the quarterbacks of IDP lineups, if you will.

Even the most casual football fan would recognize names such as Ray Lewis or Brian Urlacher. The same can't be said for Jared Allen, Roman Harper or any other high producing defensive lineman or defensive backs in the league.

A solid linebacker corps is essential in having a successful IDP fantasy season and the position generally runs deep with fantasy point producers but precious few reach the lofty level of top-tier elite players.

The league wide shift to a more RBBC (running back by committee) approach has altered the way running backs are looked at and drafted in today's fantasy realm. And the IDP side of the ball has also seen a shift in how often and when certain positions should be targeted in fantasy drafts.

The specialization of the linebacker position has made it a smart strategy to draft as many high point producers at the position as early as possible. Distinguishing three down players from those that leave the field on passing downs is vital when examining and then ranking linebackers.

Some situational players may be poised to take that next step to an every down role and being ahead of that curve can exponentially help an IDP owner to dominate their league.

So, let's take a look at a few linebackers that are ready to step into fantasy stardom and lead IDP teams to 2013 glory.

Perry Riley, ILB, Washington: Riley has been rock solid since replacing Rocky McIntosh at inside linebacker prior to Week 10 of the 2011 season. In the 25 games that Riley has appeared as a full-time player, he has amassed more than 200 combined tackles.

Due to injuries suffered by Brian Orakpo and Adam Carriker, Riley was also utilized in quite a few blitz packages last season, as Washington had to get creative with ways to generate pressure on the quarterback. He responded with 3½ sacks while also holding his own in coverage and was credited with seven passes defended.

Riley is the heir apparent to London Fletcher, if and when, he does finally decide to retire (I'm not holding my breath while waiting for that) and is due for a big bump in fantasy value once that does occur. At 6-foot-1 and 240 pounds, he is a slightly bigger version of Fletcher, and, once he takes over as the lead man in the middle, he can...