Gracie Barra Bristol, (BJJ), Can Sönmez, Bristol, UK - 28/03/2013
When moving around to north-south from standard side control, start by shifting your grip. You'll need to place one arm by their near hip. A useful tip from Braulio is to anchor your hand flat on the mat by their legs, elbow near their bum. If you instead grab their gi or their trousers, they will be able to follow you with their legs as you turn. If you put your hand in the way, that acts as a barrier, meaning you can scoot around but they can't scamper after you. Your other hand will normally wrap under their far shoulder.
As always with top positions, you must make sure you are maximising the weight you're driving into them. Stay on your toes as you walk around, also establishing solid grips with your hands. Press your chest down to turn their head to one side: that is a good general rule of thumb from top position, as if you can turn their head to one side, it is tough for them to turn their body in the other direction.
As ever, there are numerous ways you can grip in this position. A common option is to basically flop your upper body onto their head, bringing your knees in. My personal preference is to move off to one side of the head, driving my weight onto their shoulder, my head low and pressing down, sprawling back with my legs.
You can also experiment with various grips. The most basic is probably grabbing under their shoulders and reaching for their belt, then pulling them in towards you. You could also try putting your elbows into their armpits, or maybe wrap up an arm, perhaps sliding your arm under the head. Another common approach is to have one arm over their arm, while the elbow of your other arm digs into their armpit.
Generally you want to keep your hips low, like in side control, but there are variations where you raise your hips, driving your weight through your shoulders. As Jason Scully over on Grapplers Guide mentioned, if they try that escape where they wriggle out and fling their legs over to take your back, raising your hips can be useful. You can then drive your forehead into their chest to stop them completing the escape.
The best place to learn about maintaining the north-south probably isn't BJJ: its parent art judo is much better at pins. In judo, the orthodox north-south is called 'kami shiho gatame', with lots of variations. For example, the above picture shows three options mentioned in an old instructional book from 1952, Higher Judo: Groundwork, by Dr Moshé Feldenkrais (not only a good judoka, but an engineer, physicist and founder of the eponymous 'Feldenkrais Method').
Scarf hold is useful to switch to if they start shoving into your neck and bridge. Turn your body, resting your torso on them, leaning into them for extra weight. You can have your knee up (to provide a counter if they start forcefully bridging into you), but be careful they can't hook that with their leg. You can also sprawl your legs out, one crossed over the other. Keep your head low for additional control.
The position is also handy for when you want to kill the near arm. Scoop up their elbow with your near hip, digging it underneath as you switch to scarf, pull up the arm, then return to side control. Bring your knees in tight and suck your partner in with your arms to remove any space for their arm. From there, shifting backwards and sliding through to mount becomes much easier.
Most instructors would say that it is very important you pull up on their arm and keep good control of that elbow in scarf hold. If they can get their elbow back and dig it back under your hip, they can start to make space and escape. However, John Will disagrees. He feels that this position wasn’t as common as it used to be, because people often have a bad experience. They go into scarf hold, pulling their opponent’s arm up...then the opponent links arms behind their back and rolls them over. The move can often be discarded by beginners as a result of that bad experience.
Finally, this can also combine well with the Saulo position I demonstrate in my side control basic maintenance class. If they are really shoving their forearm into your neck, you can go with that pressure but still keep control, 'connecting the hip' like Saulo advises.
Teaching Notes: North-south is my personal favourite transition and I also often shift into scarf hold. I've combined north-south with knee on belly in the past, but I think knee-on-belly is better served by a separate lesson. I'll have to think of what to combine it with: perhaps reverse scarf hold and a transition into mount? That might be too much for one lesson though.
Today ended up being quite conceptual, which is hopefully useful. I know I like general principles that can be broadly applied, but then not everyone likes to learn in the same way. I'm at the point now where I'm confident on at least one lesson for each position, but still working on how best to introduce techniques beyond that.
That's one of the downsides about only teaching once a week, as I can't test things out as regularly as I'd like, but then teaching more often on a regular basis at this point would essentially become a job, so I'd need to get paid to make it viable. Hopefully some day in the future that might happen, but for now once a week is cool. :)