Yahtzee, Yahtzee - if you REALLY hated CAD, you should have just ignored him. Now, many other people are going to go to his site, and see why you hate him - you've probably given him more fans.
I've read CAD. It's not the best. It's not that funny. Yet I read it from time to time (as does Yahtzee, evidently). It doesn't cost me anything to read, and occasionally, it has a good joke or two. I wouldn't pay money to read it, of course, but he's not asking for money to read it.
I've read worse than CAD. I've read better, but I've read much, much worse. CAD has gotten better with time, still by far the best, but it's not putrid or vile. I've never had any problems with the "huge" amounts of dialogue either.
Buckley is trying to flesh out the characters of CAD. His comic probably didn't start out as a drama, but he wants to make it one. He wants to take it beyond what it currently is, and he needs Drama to do that. Maybe it's not a smart move, sure, but it's a least something new-ish or at least different from the vast majority of webcomics out there (at least, gaming web-comics).
I read quite a few web-comics - most are hit-and-miss. If people REALLY hated CAD, then why bang on about it? You're just driving people to Tim Buckley's website.
I don't hate CAD. I don't love it either. I read it, mainly because I want to see how it ends. Like the Harry Potter series (which I lost all interest in after I turned 12), I don't necessarily read it because I love it, but because I just want to see where it goes.
I've never met Buckley. I sometimes read his news posts. I can't say whether or not he acts like a jerk or a reasonable guy. I can say this about him - his comic doesn't descend into crass gay-jokes like many other web-comics out there. His comic has... changed, and some like that and some don't.
If you hate it THAT much, stop reading it. Nothing hurts a comic artist more than to be ignored. If you like it, continue reading it. Remember, everyone has a different idea of what humor is. Some like "Hitchhiker's guide to the Galaxy", some don't. Some like "Australia's/UK's/America's/ funniest home videos", some don't. Some people like "jackass" and deserve to be buried alive.
Don't like? Leave him alone. Simple.