Was rolling today in the gi with a dude that's probably got at least 30lbs on me (I'm 5'10, 180-ish) and I'm in the bottom closed guard after losing the mount by a trap and roll. I'm usually comfortable in the bottom closed guard, but today my opponent played something I wasn't used to.
Rather than try any of the more conventional passing techniques where you keep distance and try to stand up, my opponent locked up a bad head and arm choke (his head was underneath my armpit, but he wasn't able to get my elbow across my centerline to block the neck with my own shoulder), stood up and tri-podded, and just continued to pressure into me while squeezing to try to finish the choke. Although the choke never came on, he opted to maintain the position to force me to make a move.
Because of the chest to chest pressure, I found I was unable to break him down by pulling my knees in. So then I tried to open the closed guard and insert a butterfly hook, but I think he stepped out or leg pummeled and sprawled his hips or something, and before I knew it I was in half guard.
What are some effective tactics for generating offense in this situation where the top player stalls with upper body controls and has zero intention to open the closed guard?