They do it several times a day over at the Refreshment Corner (Coke Corner) where the piano player is. Sometimes Peter Pan is also with them.
NO... It is done only once a day. Since the beginning of Summer it has usually been at 1:00pm.
It is cancelled once in a while (Someone out sick). Or the time changed (12:30pm yesterday) due to the Parade being moved up because of the Halloween Party.)
I've seen it several times before. . . it's entertaining. I know it's supposed to be for little kids, but there have been rare occasions when Alice would have teens or younger adults play, during my AP days, I even got dragged into it once(quite literally, IIRC. . . but I did make sure I was the first person eliminated. . .)