Yes, we did talk about this exact same issue four months ago, back in the wake of the loss to Iowa State (remember when we thought that would be the nadir of the season?). Unfortunately, the problem hasn't gotten any better since then; if anything it's gotten worse. So let's take a look at the recruiting classes year by year.
2007
The 2007 class would have been redshirt seniors in the 2011 season, but only nine made it that far. Reisner, Sandeman, and Ballard never used a redshirt year at Iowa, but they also used their entire eligibility. Bulaga and Sash left with eligibility remaining, but they left to play in the NFL, which is the sort of early departure we can certainly live with (though, obviously, from a purely selfish Iowa fan perspective, it would be far better for us if they'd stayed for their senior seasons). That still leaves 7 players (out of a class of 22) that left the Iowa program early. Most of them were gone by the end of their second year on campus. (That's a persistent theme in this analysis, but it also makes sense: if a player leaves within two years, he should still have (at least) two years to play at another school, which is enough time to make a move worthwhile. Of course, this assumes that the move is of the player's volition, which has been the case with most of Iowa's departures. Clearly, cases like Everson and Satterfield are very different beasts.)
RUNNING TALLY: 7/22
2008
The 2008 class should have been the one providing seniors and redshirt juniors to the the 2011 team, as well as redshirt seniors to the 2012 team. At this point, only ten of those players figure to be around in 2012 (and that assumes Mossbrucker will come back for a third-straight year as a benchwarmer kicker; I guess there are worse ways to earn a free education). Herman and Prater never redshirted and completed their eligibility in 2011, while Reiff has opted to go pro. Again, those are perfectly acceptable departures. Unfortunately, there have also been 12 other early departures from this class (almost half the class), which is less acceptable. Most of those twelve were gone within two years as well, though Robinson and Hampton departed after their third year (2010) and Lowe left shortly thereafter in the wake of the rhabdo incident.
RUNNING TALLY: 19/47
2009
Another hard-hit class. This class should have been redshirt sophomores and juniors in 2011 and redshirt juniors and seniors in 2012. However only 12 (out of 20 signed recruits) will still be around next year. Of the eight departures, most were gone within a year.
RUNNING TALLY: 27/67
2010
The 2010 recruiting class is the one that we were counting on to be the backbone of the Iowa program going forward (given the immense attrition in the 08-09 classes, as well as the alarming number of players in those classes who haven't panned out, which is a separate but also important issue in this matter), but it began to show warning signs of the same old attrition problems earlier this fall (already four departures within a little over a year) and those warning signs turned into a blaring klaxon after the recent departures of Coker and Derby, two of the signature recruits from this class. So within two years, 6 of the 22 members of this class are already gone. The good news is that number still represents an improvement from the previous years. The bad news is that it also still seems a bit high.
RUNNING TALLY: 33/89
2011
And finally, the most recent recruiting class. This class hasn't even been on campus for a full year yet and already 5 of its 25 members have departed (or, in Coe's case, never made it to campus in the first place). Like the 2010 class, this group was meant to be instrumental in helping Iowa emerge from their current morass of mediocrity. That a fifth of the class is already gone is a little alarming.
RUNNING TALLY: 38/114
38 is a perfect 33% of 114, meaning fully one-third of the players Iowa's signed in the last five years have left the program early. Three of those players (Bulaga, Reiff, and Sash) left for the NFL, while another three were essentially the victims of career-ending injuries (Vier, Heiar, and Hundertmark). That still leaves 32 players who left for non-NFL draft or non-serious injury reasons.
A few additional thoughts:
* A few positions have suffered more than others, obviously. Among those 32 departures, 8 have been running backs and 6 have been defensive linemen (those figures also do not include fullbacks or players listed at another position who might have been transformed into a defensive lineman during their careers, such as Dezman Moses).
* At the moment, I'm not terribly interested in assigning blame for these outflux of talent. In part, that's because these players have left for a multitude of reasons: some were kicked off the team, several left in search of more playing time, some had issues arise close to home, and a few just needed a fresh start. There's no catch-all explanation here: it's not just bad luck, or just Ferentz driving kids away, or just Ferentz recruiting "bad seeds." That said, saying there's no magic bullet to explain Iowa's attrition problems also doesn't absolve anyone of blame, either. 32 departures (an average of just over six a year) seems rather alarming and is the sort of figure which should prompt some soul-searching and analysis of the efficacy of current methods of recruiting and retaining players.
* On the other hand, "seems rather alarming" is not a definitive statement and that's because I don't feel comfortable making a definitive statement until I see some hard data that compares Iowa's level of attrition to attrition at its peer schools. Given the difficulty in finding comparative analysis data like that, it looks like I'll have to sift through the raw data myself (which I intend to do in the next few weeks). Then we'll have a better idea of the true extent of Iowa's attrition problem.
* On the other other hand, we can also certainly say that it is a problem at this moment because a problem like Iowa needs to keep attrition at relatively low levels in order to compete at a high level. It's hard to be a developmental program if you spend so much time having to start from scratch. Several Iowa recruits are guys who won't be able to perform at a high level (or perform much at all) until their third year on campus; when those guys depart within a year or two, all of the time spent recruiting and developing them becomes wasted time, effort, and resources. (In this light, Coker's departure is less painful, since Iowa was able to get 1.5 years worth of good production out of him; this is a very cynical view, admittedly.) Recruiting and retention will never be a perfect system -- some measure of attrition is inevitable -- but losing 1/3 to 1/2 of every recruiting class within a few years does not seem like a successful formula for winning unless you're simply replenshing those departing faces with new high-end recruits.
* Which brings us back to the point I mentioned a few paragaphs ago: these recruiting classes are suffering not just from attrition but from several whiffs on player evaluation. Getting back to the 2010 class, while it's definitely problematic that 6 of its 22 members are already gone, the good news is that still appears to have the potential to be a very productive class: I think at least 12 members of the 16 remaining members will be in the 2012 two-deeps (Donnal, CJF, KMM, Scherff, Shumpert, Davis, Hitchens, Kirksey, Lowery, Miller, Morris, and either LTP or Hardy, possibly both). The 2008 and 2009 recruiting classes might be providing that many players to the 2012 two-deeps combined.
Of course, It's also worth noting that right now we don't yet know if the 2010 players are genuinely much better than the upperclassmen ahead of them (as we saw from several of the 2006 and 2007 players that formed the foundation of Iowa's teams in 2008-2010) or if they're just better than the admittedly low bar set by the 2008-2009 players. After all, someone has to fill the depth chart... We won't really have an answer to this question until the 2012 season gets underway.
Still, the point remains: failure in player evaluation coupled with failure in player retention is an utterly toxic combination for a program like Iowa. The margin for success here is thin already and it's hard enough for Iowa to bring in the blue-chip talents that it does get. It can hardly just slot in a few more when new holes arise. I think the Iowa coaches have done a better job of recruiting in 2010 and 2011 (and so far with the 2012 class, as well). On paper, they appear to be a talented bunch: they have decent (and sometimes quite good) star rankings and solid offer sheets from other BCS programs. Several of them have already flashed talent on the field as well. However, if they continue to struggle to retain that talent, middling results are going to remain the most frequent outcome for Iowa football.