Alright, everyone knows I'm a Lesnar hater and Fedor nuthugger. Out of respect however I usually choose to back my hate and love with facts and historical evidence.
I've got a question for Lesnar fans to answer:
Where is this extreme learning curve that Lesnar apparently has?
He didn't look any better technically against Couture than he did against Mir. Infact, Couture proved that Lesnar's wrestling is overrated. With a massive reach and weight disadvantage, Couture still neutralized Brock's take downs.
His standup didn't look any better either. Infact, in Mir II he didn't want to stand with Mir at all. Some crazy improvement huh? He did throw a leg kick or two, so that's something.
Now he did utilize wrist control more actively in Mir II, but that was due to respect to Mir's ground game. In the first match Lesnar came out very cocky, and with the help of a bias ref he paid for it.
I will give that in that one match, Lesnar's game plan seemed to compliment how terrible Mir's game plan was. That is measurable improvement. Props to his coach.
But we're not seeing this wild improvement from Lesnar - I don't take it seriously when people say "in a few years, Lesnar will be unstoppable."
People thought that a lot about Sapp too. Lesnar has only proven to be one-dimensional, his submission game and his standup have not improved.
Some fighters simply cannot adapt. It's tough to admit, but look at Sapp, look at poor Maia, look at Houston Alexander. These guys work on their stand up or ground game respectively full time to try to improve. But do they? No, it just does not come naturally for them.
If you watch one of Maia's first fights, a striker is coming at him and he throws two predictable high kicks. This is the same mistake he makes years later against Marquardt. Yet he's had top-tier training with world class muay thai strikers.
It's possible Brock will improve and become a well-rounded fighter. But at this point there is no evidence for that, and this mentality is getting a little crazy I think.

