Read "Cycle of Lies" and "Wheelman" and all your questions will be answered.
It was not a level playing field because Postal/Discovery had the process down to, no pun intended, a science with the best people in that business. It was, however level because in order to compete one had to take some exotic stuff to stay in the game. If you were not willing to do so, find another job.
Take note: virtually every rider who left Postal/Discovery and rode for another team later got busted. That's how good they were.
Having seen some of this first hand, it is one different world.