Originally Posted by
MasterKiller
I would wager a lot of that has to do with him just knowing how to position/control his body, or people not doing the technique exactly correct.
While being flexible helps, and certainly can buy you some time, it's not going to save you against someone who knows how to perform the submissions properly.
For example, I have very flexible shoulders and it is very difficult for someone to tap me with an Americana, mostly because people get carried away trying to crank the arm and forget to slide it down low before attempting the submission. But, when done properly, my flexibility is neutralized.