Was chatting with a guy at the gym the other day about exercise routines when he pointed out that the woman who had just left was particularly fit. I mentioned that I had once lost a leg lift contest to her, and added, "And I'm the kind of guy who never challenges anybody to anything unless I'm absolutely sure I'm going to win."
He responded, with a bemused glint, "Compete with her? Heck, she'd be nice to....be married to."
I've head that general sentiment expressed by any number of guys, in any number of ways, about any number of women. But that was probably the most gentlemanly way I've ever heard it phrased.