Personally, I think the descriptors, "well coached/ hard working" are extremely overblown. While I definitely agree that Iowa's players are probably better coached and managed than most, I still think raw talent plays a much bigger role than most people, including some Iowa fans, want to admit.
For example, Bob Sanders was a freak. Yes, his 40 time improved dramatically while at Iowa, but his success is not just a product of will and determination. There are probably thousands of football players out there with the will and determination to work just as hard as he did. Virtually none of them have any hope of equalling his results.
I think the reality is that Iowa's staff does a great job finding under the radar athletes. I also think they tend to avoid obvious head cases. In turn, you have a lot of motivated athletes under one roof. Couple that with excellent coaching and the results speak for themselves.
The NFL is where "hard working" and "well coached" go to die. They're just not nearly enough. Yes, most standout NFL players are hard workers and well coached, but that doesn't begin to account for the freakishly elite level of athleticism required to succeed at that level.