Here Chris Herzog head instructor at 10th Planet Jiu Jitsu Rochester New York demonstrates a very effective escape from Side Mount. On his way out he shows how to land the Darce from the bottom North South position.
You have to be careful to protect your arm that is at your opponent's neck. If you are not ready to bring your arm in tight to the T-Rex position they could catch you with a spin-over-your-armbar.
The Darce from the bottom position is sneaky. Most of the time when your on top and your opponent is fighting to get out from under you there is no danger of being submitted. This is one of those unorthodox techniques that can catch your opponent off guard if you pull this off from the bottom.
