I finally got to see this fight this past weekend.
No doubt, Lesnar is a beast. Mir was smart about it, knowing full well he was getting taken down at will. Mir is amazing on the ground anyways. Mir fought a smart fight, knowing he'd have to take on some GnP by Lesnar until he found the opportunity for a submission. It came, and then game over for Lesnar.
Mir looked good. Is he back to where he was? Hard to say........I don't think he had to be his old self to beat Lesnar. I think the next few fights, as long as they are against some more experienced, quality opponents, will tell the story.
I have come to the realization that Frank Mir is my favorite HW fighter. He is the complete package, at least when he is healthy. I'd love to see him take on Sylvia in a rematch, and then I'd like to see him against a BJJ guy, like Big Nog or Werdum. Those three fighters would put him to the true test.