The Armbars. Armlock. 十字固. It's the meat 'n potatos of BJJ and submission grappling. It's the one
submission you taught your girlfriend and/or 2-year old son. It's the move you demonstrate at cocktail parties (we know you don't go to cocktail parties, grappler). It's the move that tells the world "I train Brazilian Jiu Jitsu and therefore I've very special." We get it, grappler. We like it too. But, finishing the armbar ain't easy, so let's learn some jitz.
Actually, I am not much of an armbar guy, particularly from side control. But, I use it when it comes up and can do OK with it (of course). One thing we all know is that finishing with it can be difficult against a very powerful or experienced (or both) opponent. There are many ways to defend against the armbar, including power gripping the crap out of your own lapel, hand, cuff/sleeve, etc. There are also many methods of breaking this kind of grip defense.
*Unfortunately the original GB video was taken down, but we have replaced it with a great vid from Ray Huxen - BJJ Brown Belt and Judo BB.
[Note from DSTRYR/SG: Grapplers, mystery solved (it seems). Here's GB faixa preta and phenom, Lucas Rocha, showing that tricky grip-break. Let us know if this one is not working for you.]