You can teach all the technique you want, but 'my bench is 75 lbs. more than yours and I'm just gonna straighten my arm out now' 100% works.
Sounds like something someone who don't know teh tech would say.
Unless you're fighting a guy who can snap your humerus in half just by flexing his triceps, aint noone getting out of a good keylock.
One of the biggest issues most people tend to have with using double wrist locks/kimura trap series, or perhaps submissions in general really, is not knowing how to advance to superior finishing positions; not knowing there are even superior positions in the first place. It's like someone trying to choke people out in closed guard just using a teepee, rather than fully locking the legs in a figure four and cutting the angle.
For that matter, another thing to look for even before that is hand control over wrist control, as it makes it much harder for a guy to roll his arm out, and puts a lot more kinks in his joints.
Another good detail; if he's really squirmy or already locked out and you're having trouble wrangling his arm in to position for a more solid hold, then, rather than try to fight arm vs arm by pulling his arm towards you, you just pin his hand to the mat, and move
his body over to his hand instead.
Heck even saku has more armbar finishes
The arm bar was something everyone knew really.
For that matter though, a lot of those finishes were set up by going through the DWL in the first place.
That's another thing really a lot of folk often fail to appreciate about the series; it's not just an isolated 'submission move', it's a powerful vector for positional advancement in general, that can be applied in almost any situation. Whether it's defending shots, or reversing from the bottom, or taking the back, or setting up concession holds.
As an example, a significant part of Gordon Ryan's passing strategy basically comes down to 'forcing' deep half or reverse half guard, by climbing up towards the guy's head or back stepping, and attacking the double wristlock from there.
When Sakuraba fought and won against monsters like Vitor Belfort or Kevin Randleman, who outsized him by at least two or more whole weightclasses, on top of being highly skilled grapplers in their own right, that was his lifeline. Whenever they were trying to ragdoll him across the ring, as long as he had a hold of that, he could stymie their efforts, constantly threaten disruptions, and eventually turn into a dominant position.