I'm not saying that no caps should exists, but obviously there are countless examples where players who shouldn't be amazing, are. unfortunately in a video game there is no stat for 'work ethic' or 'heart'. Adding player personalities to the game would be a great addition, but the NFL would never sign off on it.
The caps that should exist should be on speed, thp etc. Things you can't TEACH. You can make an inaccurate qb accurate but you can't make me throw the ball as hard as Peyton Manning. Sam Shields is a perfect example of this. He was not developed properly in college but had elite physical gifts. Now in the Pros he is developed properly and becomes something special. In the game, despite his "physical gifts' he would still be rated as D potential because once set, it's set. His potential to learn how to play like a corner (instincts, angles etc) is unlimited. His speed, general athleticism etc, isn't.
The thing I hate about it is, that player NEVER gets better. Once you know the potential of a player isn't A you cut him. So i guess i agree with you that it should be hidden.
I guess it peeves me that there is no emphasis on developing players in franchise mode. If he has D potential, he is cut, despite his 4.2 forty and 40 inch vertical.