I like Jandek on Corwood too. That doc is pretty divisive it seems. The way I see it, the film folds over on itself: the first half is people speculating about Jandek, offering fanciful (or... um, STUPID) interpretations, and projecting all kinds of personal desires and inecurities onto his work, the result being a probably completely inaccurate portrait of who he is; the second half reveals him to be an incredibly self-aware artist who enjoys fucking with his audience and who staunchly refuses to disclose anything about himself. And the kicker is, that isn't quite accurate either. So... I think it works.
I missed Kill Your Idols on that list. It's true, that movie is awful, judging from the bits of it I saw on IFC or Sundance or whatever. A complete and utter piece of shit.