Alright, clickbait is out of the way. But not really.
I figured I'd throw up the bat signal to guys like Cecil and our other Martial Arts enthusiasts about the sometimes controversial subject of leg locks.
A number of MMA fighters and even BJJ competitors do not play a leg lock game. I think even MMA fighter Vinny Magalhaes once famously said "Leglocks don't work" (before he subsequently had his leg broken by Australian BJJ player Craig Jones) and his opinion isn't by any means uncommon. I'd heard that some guys would not tap to leg locks whatsoever (which seems risky to me) because they'd always been viewed as a "dirty" technique.
Nevertheless, the inside heel hook is possibly one of the most devastating joint locks in the sport of BJJ in that you can totally twist a persons knee to the point of rupture of multiple ligaments. You can quite literally cripple someone for life with a heel hook in a way that is only possible in few other submissions.
The potential for damage/injury aside, I'm interested in looking at leg locks from a defensive standpoint. I tend to see them as the "anti-grappling" solution. They seem to have evolved for the purpose of and been popularized by submission only grappling tournaments, and especially by guard players, who tend to not play as much wrestling/judo.
You still do occasionally see them in MMA fights, where ostensibly you must deal with getting punched in the head and some guys have used them to varying degrees of success such as Rousimar Palhares, Ryan Hall and I seem to recall Beneil Dariush basically breaking Tony Ferguson's leg with one.
Nevertheless, you must deal with strikes in a real fight and if you're talking about a very serious situation where weapons can be involved, you really REALLY need to be careful of letting your opponents have free access to both of their hands.
To me, leg locks in a weapons based environment sound dangerous, and leg locks for anything not rising the the need to cripple or maim someone seem like a difficult position to defend legally.
So my opinion is actually...yeah...leglocks don't work. They're incredibly useful in competition, and can be used to set up passes, sweeps etc and often you find them from half guard, butterfly guard, and especially against a much larger opponent and if you play competition BJJ, then at a certain point you will need to learn how to recognize and defend them, but if you're playing BJJ as a supplement to a strategy of self defense, then leg locks are probably of limited value.
That said, I do love me a good leg lock while playing the sport of BJJ.