I also didn't get the sense that he "devalues" the Menoeceus, but rather sees the two texts as doing two different things.
I know that's the word Todd used but I agree with your direction Don, and am reading Todd that way too, that he doesn't really mean "devalue" except in relative terms. Where the letter to Menoeceus speaks precisely I would accept it as authoritative over even Torquatus or Velleius no matter how detailed those others are. The problem is as you say that Menoeceus was written more broadly under circumstances where the recipient could be expected to fill in the details for himself, and we tend to jimp to conclusions from our own context rather than from the context that Menoeceus would have himself.
These comments have been very helpful and i am going to rework the article further in a "why does binary analysis of body/space and pleasure/pain really matter" direction.