"Parading" must mean something different to you than it does to me, then. I'd be wary of taking those sorts of secondary sources too seriously. It is not very difficult to get academics to say mean things about each other.

True but if this is more than calumny, Feyerabend was taking the theorem to mean way more than it meant about our ability to do calculations.

He doesn't appear to ever have written about it. This is a very odd way to criticize him. Why not focus on his published work? He wrote a lot about QM, so his purported total lack of understanding should be evident in that body of work. Much better than digging up some rumors that you can't even provide a reference for. (The commentary that you're referring to appears to be rather well hidden, by the way.)