My take on it, if the other guy has a conservative
Cham Jang/ "Sunken Elbow" structure, it will be almost impossible to catch or break his elbow with almost
anything...
The idea, if somebody is throwing wildly in the first place, his elbows are stretched out, and therefore open. You have to practice timing, and throw at where the elbow
will be
at it's point of maximum extension, else you crash your "
Pau Chui Ship" on his "Elbow Reefs"...
Gwa Chui,
Laap Sau etc can be used to corral or "fix" an opponent's elbow in position...
That being said, in her video, Mok kweilaan
Loi Si can be observed to be replacing the scissor-action
Gwa/Pau Chui with a
Chyun Laap/ "Drill-Seizing" hand into a
Jong Chui/ "Uppercut" beneath the captured arm, then turn
Fo Jin Chui/ "Fire Arrow Punch" like (almost) everyone else...
My take on it, at her height, she wasn't going to hit anyone with many
Gwa Chui's, and
Pau Chui could be seen as requiring (a masculine proportion of) upper body strength. Therefore, as WFH probably wanted his
Gung Fu to be a positive experience for her, he then adjusted it. The martial arts are full of individually tailored, practical adaptations such as this...
Thumb up, we're striking with the Radius Bone, so, some get power with overhead follow-through, and some get power by rotating the fist to horizontal as the bridgehands contact. While rotation has advantage in protection of your own bones while maximizing shearing action, full-arc follow through has different advantages in terms of leverage, especially striking more substantial targets...
Then, there is the issue of training longhands at full extension, for maximum dynamic range development, then shortening a bit for usage, increasing speed, power and control, while simultaneously protecting the fighter's gates by occupying the space inside the bodyline boundary...
Best,
Michael