Nope, no, uh-uh, no way, no how! I can think of, oh, about a million more preferable ways to get more stamina! And, a hundred more interesting activities to expend that stamina on. However it is all for naught without the genital equipment.

Yes, I am guilty of anthropomorphism.

What advantage does the female gain by eating the male? I imagine food for sure but is there something else as well?

Food energy at precisely the time when she is about to invest a lot of it into making eggs, perhaps.

But then she might not necessarily need to gain any specific advantage, in that eating the male may not be a specifically evolved adaptive response. It could just be a side-effect of her regular predatory instincts, to try to grab and eat anything small enough that comes close enough to her jaws, and the males just happen to get caught more easily than regular prey because they’re concentrating on something other than getting away.

I looked at your blog for the first time after listening to you on EconTalk. It seems absolutely fascinating

Yes, it’s a thing. You can find it on Youtube and Wikipedia.