3 Part Technique - Know the consequences of your attack. For example, you must be aware of all of your opponent's available reactions for when you assume 2on1 Control over his arm: (A) If he does nothing, gain more by switching for Cross Arm & Belt Control and the sweep. (B) If he steps up on the same side as the 2on1, Hook Lift him into X-Guard for the sweep. (C) If he steps up on the other side, take the obvious Hook Sweep from Butterfly. (D) If he crawls away backward, chase his retreat and throw yourself into an Armdrag to take his Back. Consider all 4 of these possible scenario as soon as you take the 2on1 so that you are ready to react with the correct next move.