What's wrong with my triangle?
I have pretty long legs and I get the triangle position a lot (head and arm in legs, with ankles crossed, legs not yet triangled) and I can never finish the triangle choke. I learned it with keeping the head down, pull the arm across, get a slight angle on his neck then triangle the legs and finish. However, my opponents always end up able to pull their heads out and pass my guard during the transition where I'm getting angle on their neck and opening my legs, right before triangling the legs. They aren't going away from their arm, giving me the omoplata, either. They just pull the head straight out then leave the arm inside my legs and go for the pass.
I've asked my instructor and he says to just keep practicing until I get the feel for it, but it's been a while and this happens all the time. Should I be squeezing harder with my legs to keep their head trapped? Should I be pulling the head down or holding on to the collar throughout the move? Or do I just need to be faster at getting angle and triangling my legs so they don't have enough time to pull out?