When Gary Cohen asked what the phrase meant, Darling said "a ham and egger is a guy who goes on the DL with a minor injury the minute he hears he's gonna be sent down".
I like the term though I wonder about it. How does ham and eggs become the symbol of a useless guy who never steps up and always looks out for himself rather than the team? To me, the phrase ham and egger makes me think of someone who sends out for breakfast and eats it on the delivery bag at his desk. But then, I lived half my life in offices. It must mean something else to baseball players, huh? I wonder what.