It's because Lesnar is improving at a scary pace. The guy has been thrown to the wolves and has done really well.
Now, do I think he'd beat Mir if they were to rematch? Yes, because Mir isn't that good of a fighter, and I don't think Brock would make the same mistake he did last time.
He won't, however, beat Nogueira. Nog's still a great fighter and will tap Brock when they face each other. Nogueira has more ways to win, and will be there till the very end.
I'm going to take this and just agree.
He could beat Mir, and Mir is getting overrated a lot lately..
and big Nog would crush him.