I don't think that Phil Hersh was saying that Michelle didn't skate well. Most people say Michelle skated extremely well. Robin Cousins put's it this way: MIchelle set the bar really high, and Tara Jumped over it.
But the way people describe the difference is this. Michelle well excellent and clean was tenative. Her skating was slower than usual, her performance was not as electrifiying as it was at Nationals, Michelle didn't "fly."
Tara, on the other hand, was electrifiying. She skated with joy and complete abandonment. She flew across the ice, while landing more difficult elements. And you know what Tara had good extension, she had nice line. Artistically, Tara had improved quite a bit in a year's time. And Tara was doing a much more difficult program. Plus, the complete joy that Tara had, she just sold her programs. (If you look at Michelle and Tara's faces while they were performing, you can see all of this)
Hersh and Cousins both said that the difference between Tara and Michelle was visibly and audibly clear to the audience; however, when watching it on television, this didn't necessarily translate well..