There have been some great posts on Language Log about constructions like this. I think "too stupid not to..." was specifically discussed in one a few months back. It generated some good discussion about how difficult it was even for linguists to notice that their instinctive interpretations of these constructions were illogical (though sometimes pragmatically correct in that they did lead to the speaker's intended meaning).

Unfortunately I'm on my way out the door and I couldn't immediately find the particular post I was thinking of, though a search for "too stupid not to" turned up another one from a few years ago.