I never count on a dockhand to be able to take that stern line and get it on the cleat as fast as is needed. My mate can do it faster because he knows the plan, and nothing will be lost in translation trying to communicate with an inexperienced dockhand. My mate secures a line to the windward aft stern cleat, then keeps the line in hand while standing in the cockpit at ready while I am backing the boat in. The mate should stand ready in the cockpit, never on the covering boards, while the boat is moving. Once I have the boat all the way in the slip, I turn my rudders so that when I make a quick stop by going into forward gear, the forward thrust on the angled rudders pushes the aft quarter up against the dock. It can be a very abrupt stop, so if the mate is on the covering board, he could be thrown into a dangerous position; he must wait for the stop before making the jump. Once stopped, he needs to be quick with the tie-up. You get only one shot at this if the conditions are bad. Not only will the wind and current push you off the dock, but the fenders will also spring you away after you push up on them. The trick is not to miss that dock cleat.