Montell Griffin made me think of this thread. Wins over RJJ and Toney in their primes (you can always discuss their mindset and preparations going into the fights, but the losses came in their physical primes) - that is the stuff of a great fighter normally, but Griffin was hardly great. Other shouts?
Actually he gave Jones fits in that fight and jones lost his cool when he finally got to him and got dq'd. It was bizarre but Jones did deserve the DQ.
McCall beat Lewis & Holmes in consecutive fights. Is he the only crazy crackhead to beat 2 top5 ATG's?
If you beat someone you prove yourself good enough to beat them. Perhaps this question will only provide cases of talent underrated v talent overrated.