it matters to who want to make sure their packet does not been seen by the target user , or by the network admin.
default way and the speed control way are sending spoof packets to both gateway and users.
cutting off gateway will only send packet to gateway, it benefit when target user have a personal firewall installed, the user still can not seen any packets.
cutting off user will only send packet to user, it benefit when there is a network admin watching gateway traffic log, no spoof packet can be seen.
Note: when you use speed control, the cut off method roll back to default since it is must send packet to both end.