Hyp, who says "all but two of them land on teh ground" ... ? That would be, IMO, an overly-restrictive interpretation of the Returning ability. After all, just because you've caught two of them, doesn't prevent you from catching the other two. Otherwise, how do you explain (for example) jugglers, who can catch all their props/throwing-toys/whatever at the end of their act, in the space of ... say ... under six seconds?
Catch with right hand (free action), transfer to left hand (free action); lather; rinse; repeat.