Points being made by me:

The short essay you linked to makes a huge leap in logic from its support evidence to its conclusion.

I outlined why I brought up zero sum, and why I think you and Mr. Henderson are invoking it's presence in the economy.

A new one:

Your claim that Krugman's shift in position is not evidence based is not convincing in and of itself. I'd be interested to see an actual response to this by Krugman or someone from the other camp, and not just evidence of the lack of evidence in a "he's a flip flopper!" blog post employing poor logic. I guess I need to do some research.