Sumi gaeshi is a throw I often attempt and fail, ending up flat on my back. But sometimes it works beautifully. Typically I grab uke’s left sleeve with my left hand (especially after ‘baiting’ with my right hand extended) and attempt the throw with that weak connection. But it’s important to put more effort into breaking him down, reaching far across his back, and to straddle his shoulder with my armpit.
If you do that, you’ve probably got sumi gaeshi. But maybe not. So you can fake an uchi mata (successfully executed, this’d drive his face into the mat—not bad in a street situation, suboptimal in competition). He’ll correct his balance, which makes turning and completing the sumi gaeshi that much easier.
With very few exceptions, it seems good to have an opponent broken down. Besides the obvious application of sacrifice throws, another “throw” I played with on Saturday is a somersault choke. I slipped my right hand deep into uke’s right lapel (cross grip), broke him down, then leapt across his back in a somersault motion: this tightened the choke and generated enough momentum to knock him over, but I need to practice it against more resistant opponents.
Another option from a left-handed cross sleeve grip is to pull that sleeve under your right arm, across your body, and to clamp down on it with your right arm. Get your right leg behind their left foot and connect yourself to uke. He’s pretty much hosed. (todo: name this throw.)
You can also pull the sleeve across—as with sumi gaeshi—and do a very aggressive o uchi gari, pulling your opponent down onto the same side as the arm whose sleeve you’ve got.
Finally, a couple words on lapel chokes from the back. Once you’ve got your over-under, you can use your under to straighten uke’s lapel and choke up on (heh) your over-the-shoulder grip. From here you can pull down on the opposite lapel with your under grip and straighten the wrist on your over grip hand. But once you’re deep with your over, you can also trade that under grip for a half-nelson, which removes his arm from play while enabling you to push your fist into the back of his neck to tighten the choke. If you’re really flexible (if I’d've been warmer I can see this working) you can use your leg to apply the half-nelson. Maybe it’s unnecessarily fancy, but the result is incredibly strong and truly hopeless for uke, assuming your collar grip can keep up with the torque you’re creating.
