Hmm, your model doesn't consider that some companies might not be able to benefit from any programmers what-so-ever because of their own incompetence (some companies are -1 to begin with).

Anyway, job search is certainly not entirely adversarial. But any negotiating process has to involve a sequence of honest signals from both sides. If one side can completely control the signaling process, that side can get the most benefit for the least cost (and the other side would choose a different frame if they could - and especially the most valuable players would make this choice).

Thus even though I eventually do want to reveal everything and commit fully to a potential employer, I expect the process of commitment and revealing will only happen as the employer also reveals information AND makes commitments to me. It's a dance. Things that allow the employer to merely get commitment and information from me without anything in return result in an undesirable negotiating process.