In your mount escape tape/DVD you advocate (in the elbow-knee escape)putting an arm across your partner's chest/neck (after getting the half-guard). Doesn't that expose your arm to, among other things, getting pushed across to the side choke? I've been caught a few times -- any suggestions? I noticed that on your half-guard tape, when you use the arm-across it's in combination with the shin across the torso (which prevents that sort of jam).
Pull your elbow back if they try to push it across. Also you should already be turned on your side, not flat on your back, and trying to regain guard. If you you are on your side, your opponent will feel like he is losing position rather in a position he can do a submission.
If you know how to play half guard with the underhook, take that instead as soon as you get one arm between the legs.