Speaking for this member of the anti-Miers crowd, you could not be more mistaken. I believe her appearance would be at best mediocre, and more likely disastrous. But if for any reason the hearings proceeded and she revealed herself to be a highly articulate advocate of constitutionalism originalism, entirely conversant with constitutional law and principles, I'd be pleasantly surprised and happy to change my view of her.
But I think the odds of that are slim and none. Based on her writings that have been made public and the comments coming out of her meetings with senators, it seems clear that she lacks both the knowledge and the intellectual skills to pull off that kind of performance in the hearings.
Go ahead and be yet another IQ test adminstrator. The smartest person I know (he's considered a genius by other professional mathematicians) cannot write a word, even in his native language.