Let me begin this with an apology for my churlishness in not thanking you yesterday for you kind words RobCor. It was remiss of me and I can only attribute my bad manners to single focus geekery on the issue you brought up. As for your Lady Fair's technique for that grab from behind, it's a pretty good escape technique and nearly identical to the one we teach for that particular attack. Shin, Instep, Nose, Groin or as Gracy called it the SING technique.
That video clip is interesting but I'm not sure if you and I agree why. I see that and think it is like watching a game of chess as they manuver around the mat and each other's anatomy trying for a hold or an advantage. I used to do this on the ground in judo in college. Mat technique is frequently overlooked in favor of the big spectacular standing throws that make the floor oscillate from the crash. Our team used this overlooked stuff to clean the clocks of our opponents again and again until a few got smart and caught up. The main thing I saw though was a fixation on the part of both of them with grappling to the exclusion of other forms of seperation, escape, and striking. I mean come on, they had those cool looking MMA half fingered gloves on to protect their hands fo strikes. Neither of them used knees or elbows to any effect either. That's part of my knock on MMA and other sport martial arts. Either they are limited by their rules (and with some reason, to prevent severe injury or death) or the boundaries of the art they practice. Can't use strikes in judo for instance. A friend of mine who is a 6th degree black belt in Hapkido used to do the paintball thing years ago when I still carried a gun as part of my duties as did he. It was fun as hell in both the outdoor and indoor version and I discovered my ninja abilities to trail, stalk, and back shoot unwary opponents. We decided to stop because we could see it was affecting our perceptions and behaviors toward use of the real thing through either reckless conduct or some other undesirable stuff because you actually die in paintball. Haven't touched it in over 20 years now. Same with the whole MMA thing it might just breed some bad or wrong responses to a real attack without benefit of a referee.
The kid's jujitsu was a real rodeo. The other adults got the flu and there was only Master Bellman and I to contain 30 kids who seemed sugared up to the eyeballs last night. I had to grab one kid by the collar and transport him, feet dangling, to the opposite corner of the mat to keep him from screwing around with another kid. Lots of promotions at the end of class so I was busy putting stripes on their belts. The blue belts got another stripe and these kids are so diligent and so good as they came back to the line up I did a kneeling bow and did an "Ooohsaa!" at them. The girl asked me why I did that, and I told her it was a traditional Japanese sign of respect for achievement that they had both earned. The boy never talks, not once. His dad is the same way, so I think it's a family trait. Great kid though, it's so rewarding to contribute to the teaching of folk like them.
The adult class had me paired with a 5' 5" 115 lb. woman who needed to be convinced it was OK to hit me harder, that I wouldn't cry. It's getting women and girls over the nice girl enculturation and wake up some ferocity that can be difficult. Our teaming was no accident because she has never worked with anyone my size before and needed to discover how different it was to have to deal with someone the size of a likely attacker. She warmed up to it after a few "No hit me in the sternum harder than that!" prompts. I also had to reinforce letting go of me when she threw me so as not to get pulled down by the force of my fall. After 3 unsuccessful prompts I held on to her gi as I went down and rolled sideways. It pulled her down and whirled her around me and onto the mat with a resounding thud. Then I put my forearm lightly across her throat and said, "This is why you want to let go and not get pulled down." She picked it up right away then and didn't repeat the error. A green belt got promoted to the next rank in that color and I told him after class that by tradition he can start wearing black gi bottoms now.