No psychic I've ever seen used a Ouija board for a reading. Not that I've been to a lot of psychics, either, but, they're not used for readings.
We did experiment with it back in the day, though, and concluded just this: I always seemed to know what it was going to say, so it needed my eyes. BUT, my friend, who had NO idea what it was going to say, seemed to be controlling it. No joke. At one point I had the tip of 1 little finger
barely on the planchette -- with no way to actually control it if I wanted to -- but it always felt like it was out of my control and the planchette was being controlled by him. But all the words seemed to come out of my head. I never understood that.
Ideomotor? Perhaps. Physically possible? Not sure.....