During Jiu-Jitsu class I frequently remind my trainees if it bends it will break. The it being any joint in the body from head to toe.
Your Jiu-Jitsu sets you up to be dangerous on your feet or on the ground. Anything you touch on your opponent should be in jeopardy instantly or within a few seconds. As Coach Matt Thornton, Straight Blast Gym founder and president says, “only one person should be comfortable in a Jiu-Jitsu match”. Meaning that during a fight you should be in a position to inflict damage while being relatively safe from damage.
Within Jiu-Jitsu there is some discussion regarding leg-locks and wrist-locks as it pertains to the rules set forth in some competitions. My thoughts are this, train to be dangerous regardless of rule set. Similar to the saying; I’d rather have it and not need it than to need it and not have it. Read the rules, develop your game plan within the rules given, and then do the best you can. Simple enough.
Without the rules you are free to do as you wish, (within the law…), so be as dangerous as possible. Study and develop a complete Jiu-Jitsu game. It it bends it will break. If someone touches you with malevolent intent, start breaking it. All of it.