Tani Otoshi > All standing locks
So last night some of the Wing Chun/MMA/eclectic guys where workingout before my class and they were playing with a standing lock that tied up both of the attacker's hands. The first thing I said when I saw this move that they were having trouble getting around was "Tani Otoshi would get you right out of that." I demonstrated and it did indeed work. They adjusted accordingly and said thanks.
Here's the interesting part. I can't really think of a single standing arm/shoulder/wrist lock that Tani Otoshi wouldn't have an excellent chance of getting you out. Especially the version shown in the video above that goes straight to mount.
Any ideas? What wouldn't this work against?