Some people can do but not teach. If something just comes naturally to you, but you don’t know how to explain it to someone else, you’ll probably be a pretty bad coach.
Others can teach but not do. It’s easy for them to understand what is happening and what should happen and convey that to someone else, but they might not have the physical ability to go execute that themselves. You’ll probably see at least a few career backup QB’s each week now as offensive coordinators or offensive assistants for this very reason.
I think he was just joking about silverware and hungry.