I've never hung out with *my* dentist, but I've crewed for (and raced against) *a* dentist... He's a great guy until the ten-minutes-to-start flag goes up, and then, whether you're on his crew or on another sailboat, he turns into the most ornery son of a bitch you've ever met. If he's got right-of-way over your boat, you'd better get out of his way. If you're crewing on his boat and he's got right-of-way over someone that doesn't seem to want to move, you'd better find something to hold onto.
But yeah, off the water he's a pretty good fella.