As I said, I'm no expert. I've hung out on some FR threads where people had some very convincing arguments against ethanol -- as well as quite a few pro-ethanol. They get quite feisty! I used to think it was a no-brainer -- now, I think the issue is more complicated.
But even if alcohol is a great fuel alternative, to produce it more cheaply from secondary sources (corn cobs instead of corn, hay, etc.) would make things even better, wouldn't it?
I not a real expert either and I also have noticed some heated arguments before (one has to wonder why we can't capture that heat).
I have been keeping an eye on Brazil and I can't imagine they are going to switch to an ethanol economy if it doesn't have an economic foundation vis-a-vis oil. But what do I know?