If you are having trouble finishing the rear naked choke because your opponent keeps pulling your choking arm down...
If you are constantly losing the most dominant position in Jiu Jitsu, then you might be missing some control details.
So last weekend Jiu Jitsu shined again in the UFC with 3 beautiful submissions on the main card: armbars by Fabricio Werdum and Demetrious Johnson, and triangle choke by Tony Ferguson.
One of the most important elements in order to become a successful finisher from the Back position is knowing how to clear your opponents defenses, a.k.a. hand fighting.