I don't think making a move in an elevator is an expression of confidence. I haven't read a specific analysis of the situation from a PUA guy but I would expect them to advice against that behavior.

I think tabooing "confidence" would end up being revealing here. I suspect yours, confidence-1, would read something like "not signalling anxiety or nervousness", whereas I'm talking about confidence-2, the anticipated probability of success, which informs the expected value of an approach.

I accept responsibility for the miscommunication. In my initial post I talked about PUAs advocating "confidence", and equated that to confidence-2. You and others have pointed out that actually some or all of the advocacy is for confidence-1, which I didn't at first appreciate. I haven't read all that much PUA stuff, so I'll accept what you've said and leave it at that.