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On a personal level I really love the signaling model. If you are not familiar, it's basically the idea that if you want to prove you have quality X, then you do wasteful and useless thing Y that someone WITHOUT X would have a harder time doing than you.
This is overall excellent, but your understanding of broader signaling theory is lacking. Your signaling model is only one of many ways education could signal ability. Read _The Elephant in the Brain_ for a broad overview of signaling.
