Rick didn't want to insult the woman's knowledge of the art, or anyone who used it. The truth was he had a lot of respect for those that could. Michonne had saved him plenty with her sword, done things that he or the others wouldn't be able to do with their guns and knives, the same way Daryl could do with his crossbow. They were all useful in their own right, and clicked well when used properly.
It was just that he couldn't ever picture himself using anything but an axe or machete if he really needed. "Uh, just never thought about it, I guess."
He chuckled lightly, trying to picture himself using a sword. "You say that but you've never seen me try to use one before. I don't think I'd like to shatter any sort of respect anyone may have for me showing just how graceful I'm not."