Yes, It's a Counterexample

Yesterday I did some more thinking about one of the main examples in the paper I'm reading, and I was convinced that it was almost -- but not quite -- a counterexample. The conjecture is (was) about N-filtered algebras because it hinges upon a result that is based on a result that is a consequence of a result that is stated for N-filtered algebras. The original paper upon which all this is based is so old that I would need to go to the library to look for it, so I don't know if it really matters if they're N-filtered or Z-filtered. But the example I'm reading about is pretty obviously Z-filtered, so I thought that there was a chance that the conjecture would hold or that there was some work to be done in contradicting it. But, no, I've just checked [McCR], and it also has a pretty straightforward N-filtration where grA is noetherian. Bah.

Mildly related woe: how do I find someone to cover my classes the day before spring break so that I can go to the southeastern sectional AMS meeting?