The point here is that M(u-v) might not know what v is, but M(εu+v) certainly does, and this is not the same as maximising an unknown utility function.

Ah, okay. I think I see better what you're getting at. My intuition is that there's a mapping to minimization of a reasonable aggregation of the set of non-negative utilities, but I think I should actually work through some examples before I make any long comments.

Do you disagree with my description of the "resource gathering agent":

I don't think I had read that article until now, but no objections come to mind.