During training this week I've really noticed some positive development in my side control. Especially the north south version where I grip my opponents pants near their hip and the other arm is over. I usually try to go for a north south kimura or a lapel based back take from here but not with that great success.
The thing is that most of my opponents allow me to turn their neck facing away from me with my ribs. I do this to get a better control of the position. However, it is actually a set up for the north south choke as well. I just suck at the north south choke. I have to try the north south choke more often.
Here is Marcelo explaining the choke. The thing is that 50% of people don't even protect their neck from the choke so you can skip the clearing of the hands