RIght, like for the shortcomings of the second portion, he goes and says that well, the King book suffered too when it was with the adults, because the idea is about childhood. And he made fine points and all, bu the idea is more of comparison, as IT without the adult segments wouldn't be half the book it is (. . .literally). The second half didn't measure up because the dialogue was pretty bad, the finale was awful, so on.
Although I agree with him about the sex scene with the kids. Now it made sense in the story, but . . . just because yo can justify something doesn't necessarily make it a good addition to the story. I always reread IT every now and again, and that portion sticks out more and more whenever I pass it each time.