Leg locks are still one of the most underutilized aspects of submission grappling in MMA. Why? The same reason many BJJ gyms avoid teaching them - Cause they are f&*king scary. But like anything else, if trained correctly and consistently, they can be successful.
Leg locks have the connotation of being low percentage, and if a submission is missed they place you in a bad position. Using that point of view, an arm bar from guard during a fight would provide the same results. - WRONG!
This will be one of the few times I will definitely say your wrong. Leg locks are, as stated before, an underutilized tool and they need to find a place within mma. I'm sure most of you have seen Paul-Harris breaking limbs without mercy, why can't others do the same?
Again it comea down to training. During a ground fight, the legs are just as readily available if not more available as the arms and neck. The legs also offer an almost countless onslaught of variations that arms don't provide (at least not with gloves and wrapped hands.)
Well guys get sweaty and it's hard to hold on - No shit, how does the arm or neck differ.
If I miss a leg submission I will be in a really bad spot with my opponent on top of me. - This goes for any submission and the key to attacking can be found within the style of Catch. The CACC style chains submissions and takes them when they present themselves. Some might say you need position before submission - well what about thinking of submission as a position? Knowing lock flows and proper locking positioning allows you to attack with impunity as well as position yourself in places where you can re-counter or escape a situation before it becomes bad.
Check out this video from the guys over at Revolution BJJ in Richmond, VA They show us how to properly tie up the legs, minimize exposure of your legs, and attack without hesitation.