For the last month or so I've been dealing with a strained abdominal muscle that has really prevented me from training at a high level. I can't work my guard game terribly much and certainly not while rolling. My rolling has been pretty restrictive and I'm only working with select people to try and keep this injury from getting any worse or prolonging it. I've been very focused on my topside game since then. Last Saturday our instructor Shervin Alavi brought this series in for us to work. (by Andre Galvao). I really like the choke but even more so I LOVE the half guard pass that sets up the choke. I'm a huge fan of attacks from side control and knee on belly so I should be able to work this into my game pretty well. Good stuff from Galvao and Team Atos.
Now reastically the bottom guy may be able to free his elbow from the lapel trap. In that siutation there is a great ezequiel choke that can be had from half guard or knee on belly. See here in this video by Caio Terra at around the midway point in the video.