Hi, I'm guilty of not keeping up with crits. I was sequestered for my own revisions, but I'm gonna make up for it. Don't kick me out, K?
I was wondering though, about the 3 chapters thing. I feel like I have great input on my own first three chapters, but a lot of it is the same, and most people will only read the required three. So I'd rather read a different three chapters of someone else's MS, with the caveat that I might not have the whole background, but it might prove more useful to the author. Unless there is some rule about that and the idea is that everyone crits the same thing.
If I like the book, I've made the effort to read the whole thing. Which means I may give fewer crits, but I think they are better.