Oh, no!
It’s bad enough if the guy is a fraud, which is most likely: He might whack you in the head, rob you, do unspeakable things to you. That’s bad. At best he’s a prankster, right?
What could be
worse is that the guy really
is Gandalf! There’s no telling
where you’d end up, with whom, or
what you’d be doing! And he has the habit of vanishing just when he would seem most useful: in a pinch! “No, really, officer, I just picked up this gentleman on the side of the road back there…” “What gentleman, sir?” “
Ulp…!” “Sir, please get out of the car, and stay right here until some nice people arrive to take you to see a nice doctor.” Ooh! Bad.