Good work Bruce! I like it.
Things I noticed:
1. This is the same attack from the opponent we think about from this movement too in our style. They could also be following in with a head-butt after the initial grab, so it works for that also.
2. To me it looks like you never really get his balance - this is really important for this movement, otherwise they could follow up with a strike. This could be because:
a) he's not really committing to the attack - it doesn't work (in the sense of getting their balance) unless the attack is committed. It'll work as a simple block without getting their balance, but I'm not a big fan of that. Maybe ask him to "really go for it"?
b) you move back a bit too much when he attacks - I find this technique works best if you play the waiting game - let them come to you, then bounce them. What we tend to do is just let one leg go back initially while leaving the weight forward, rather than step back, that moves your head back just enough so you don't get head butted as they fall in front of you, but keeps you close to them to do the technique at the right range.
3. In our form we bend our legs as the hands come down - and put a bit of your own body weight into it, which should result in them folding in front of you, that's the second half of this technique (what goes up must come down!) (when you do your pull down at 0.39 you don't bend your knees, instead you bob forward slightly to get body weight into it - maybe try doing it by staying upright and dropping the weight using the legs?
4. If you raise your hands shoulder width apart, like most Tai Chi forms I've seen, then this technique doesn't work exactly like the form because your own arms hit the underside of their arms and that gets in the way of pushing them down afterwards. In our form we raise the arms up and bring the arms to the centre at the same time to bounce the opponent (peng), then separate them (split) and lower them (pull down/shock), that way you get the initial bounce, then split, then splat! If your arms raise shoulder width in the form then you might want to think about changing the form here, because that doesn't work,(well ok, 'doesn't work' is a bit strong. Maybe better to say 'modified more for health and less for martial...'
)
I'll try to do a video on Monday to illustrate the above points, because it's hard to convey all these subtlties in words. You are right about there being no 'follow up' move in the form - one thing my teacher did was to create a little follow up sequence for throwing the person that links straight back into the form at this point. I learned it, but it's a hell of a tricky throw that works purely on momentum, and I find it too difficult for me - fine for him, but difficult for mere mortals, so don't do it much myself - maybe as I get better/older it will become part of my form
I'll try to show that too on video, but it's super difficult. I prefer, 'just hit them in the head'
Edit - just reading that back and it all sounds very critical - sorry - don't meant to sound like that - on the whole I liked it.