I'm not going to jump all over you here, but basic math shows that the Show could institute these exact percentages, if they wanted. The top 100 represents 30 team's prospects over multiple drafts. At any give time, in the game, the minor leagues have upwards of 75 players.
And besides, who cares about percentages? That isn't the problem. This can be done easily, based on the numbers the game already uses. With 5-ish rounds fo the draft, each draft adds approximately 150 new players to the game (per year in franchise mode). With some time and creative programming, there is no reason the Show could not mimmick the star-to-bust ratios of real life.
What is being said in the thread, is that it would be nice to draft guys based on attributes, and see what happens when they are mismanaged in the system or injured, or even underdeveloped.
In fact, NFL Head Coach '09 does this to an extent. When a player gets drafted, he has a non-static potential rating. With injuries and bad performance comes a drop in the potential rating. In many cases, misused players never play up to their potential.
So, these percentages is not what anyone is after, it's the ability to see that 144th pick in the draft out play his initial ratings and become a star or that 3rd pick in the draft go the way of Antone Williamson.
In all honesty, my math sees this being a fairly easy modification. I would like to see your math if you think it can't be done.