I think the bitterness comes from the way sports evolve. The greats of the past didn't go to MIT and hop into a wind tunnel to study their aerodynamics. Frame materials like carbon fiber didn't exist. It goes on and on. If I were a great athlete with a bunch of records, I'd feel a little put off at how athletes use technological breakthroughs to perform better. I'd want it be be purely about the man, but that's not the way it is or will ever be again I guess.
Baseball (which I know more of ATM) is the same. Wonder why more guys are hitting 30-40 HRs a year? Laser eye surgery sure helps. When a guy can walk out the door of his local ophthamologist with fighter pilot vision, he's a threat to go yard. And that's legal. Nevermind the stuff the MLBPA sweeps under the rug.