A funny Fantasy short story about a telekinetic who loses his power when he thinks about it

Question

I read this short story in a collection, I'm not sure when, 20 or 30 years ago, I think.

People are playing darts. There is a prize for the winner. A newcomer comes in, and claims he can beat them all. And indeed, every dart he throws hits the bull's eye.

Also he has only ordered a single drink and keep sipping at his glass and the people realise that their glasses get emptier while they don't watch.

The others realise the newcomer is a telekinetic. Under threat of beating him up for cheating and stealing drinks, they compel him to explain how he does it. He tells them that he doesn't guide the dart, but makes the bull's eye attract it. And makes his glass attract the drinks. So they insist, they want to how he does it. So he starts thinking about how he does it instead of just doing it.

But after his attempt at introspection, he finds out that, instead of making various spots attract things, now only his skull is able to attract things...

Answer 1

This is The Centipede's Dilemma, first published in Callahan's Crosstime Saloon, a collection of short stories by Spider Robinson.

[This story] concerns a psychic who uses instinctive telekinetic powers to cheat at darts, and is foiled when another character triggers hyperreflection in him.

_{^{Per Wikipedia}}