Several conversations that Feynman and I had involved the remarkable abilities of other physicists. In one of these conversations, I remarked to Feynman that I was impressed by Steven Hawking's ability to do path integration in his head.
"Ahh, that's not so great," Feynman replied. "It's much more
interesting to come up with the technique like I did, rather than to be
able to do the mechanics in your head."
Feynman wasn't being immodest, he was quite right. The true secret to genius is in creativity, not in technical mechanics.