Did you not read my post? IRL no one knew those players had that kind of talent including themselves. The difference between RL and Madden is that IRL no one knows how good someone can really become but in madden they are all knowing. They premade the drafts to have those late round sleeper players like Brady and Davis.
If real players(not premade rookies) perform IRL then they get a roster update. In madden you cant do a roster update on premade rookies because EA already knows exactly how good everyone can become. They choose who the sleepers are because if they didnt then EVERYONE would be a sleeper and it would ruin the game.