ive provided some proof man. you just didnt quote any of it.
my opinion is based off watching there fights man, its not bias,it cant be i dont like one of them better than the other.
watch diego fight with karo and then watch gsp's fight with karo, watch how much better gsp's wrestling is and how much more damage he does to karo. karo got battered vs. gsp. gsp wasnt even as good then.
there arent any real other comparasins because diego has never fought anyone who's held the title ever, the guys gsp beats.