Mike was opinionated, sometimes a little blunt, still honest and genuine though. That might have unintentionally rubbed some guys the wrong way. He sets very high standards for himself, definitely a perfectionist, as Ed said.
I think he was misunderstood by some. His critical observations came from experience,(he was a professional bowyer) and the ideal of seeking perfection, both in his work and for others in their own. If he thought you could improve an area in your tillering, he wasn't shy in letting you know. He might have nit picked the details on a couple of otherwise really good bows, but he was usually right, and if you listened to his advice your next bow would be even better.
I never got the impression his opinion was coming from a mean place.
He is one hell of a good bowyer though, and a smart guy. I hope he comes back.