In "Saturday Night Fever" scene Robert Hayes throws his white coat then it comes flying back at him...if you look carefully you'll see the hand and arm that throws it at him.
It's been a while since I've seen the movie, but isn't the Saturday Night Fever scene you described supposed to take place in a dance club or something? If so, isn't it pretty logical that the hand/arm you saw throwing the coat was someone else in the night club? Like I said, I could be wrong about the whole scene because it's been a while.
Actually, if you watch the movie, it's pretty obvious that he was throwing the coat at him. It was HIS coat, and you could tell by his arm movement that he was aiming in that general direction.
Actually, I don't think that this was a Slip-Up. I think that he threw his coat aside, and someone threw it back to him. Maybe his coat landed on someone or something like that. There might have been a reason that the coat was thrown back. I think that since that wasn't really a Slip-Up, showing the arm and hand throwing back the coat wasn't a Slip-Up either.