Technique Help Needed - Inverted triangle from bottom side control?
I've gotten to this inverted triangle from this bottom side control position in which I've already caught his far arm with my legs. I've made it here a few times while rolling but am unable to get a finish or sweep. My 1st instinct was to hook his leg the way I would with a regular triangle but that just makes it easy form him to hop through the N/S position right to the other side - where I lose the position.
I feel like I must have something but the only option I can see is to post up to my hand for the sweep (with inverted-triangle intact) and finish from top position. To make that happen I need to grab his right arm in front of his face a with my left hand to take his base away - then I can post up on my right hand & sweep easily. However, if he protects his hand by putting it under my legs (as in the video) it seems like he has too much base & I've got no where to go.
It sure feels like I have an advantage when I synch up that inverted triangle. Can someone please let me know if there is anywhere to go from here?
http://youtu.be/VGQzCpH6TfU