Originally Posted by Guy
It's not the ORG, its the FIGHTER.
I completely agree.
Case in point:
Anderson Silva in Pride(3-2-0): To be honest, he didn't look all that impressive when he was there. Heck, he lost to Daiju Takase who was 4-7 going into that fight.
Anderson Silva didn't look good until he went to Cage Rage after he left Pride, and then became a monster when he came into the UFC.
He evolved, got better, and was probably more comfortable working in a cage.
If he fought the best Pride had to offer when he was there at the time, he would've gotten demolished I think. After having improved over time as a fighter, if he fought them again he'd probably murder many of them.
As others have said, these guys are aging, and either improving their skillsets, or are standing still and getting run over by fighters who are continually improving.