From what little I watched of the form, he seems to be doing it in a PRC Wushu way. The whole arched back, butt-out is a giveaway that it isn't traditional. Check out other PRC Wushu videos and you'll see it in there. A stance done in the way demonstrated by Alex Huynh (The PRC Wushu way) looks far more dynamic then the traditional stance. Therefore, my guess is it's done to make the person look more pleasing to the eye. Judge Pen, if you go to a Longfist school, it's likely you'll see beginner students doing this and getting corrected. Unless you are used to deep and wide stances, it relieves the stress if you stick your butt out and arch the back. Try it out and you'll see what I mean (unless you are used to deep and wide stances). Giving in to the body’s tendency to stick the behind out and arch the back is incorrect though. Therefore, students need to remove that habit. A good stance that is deep and wide will keep the back straight and the behind in. The person may lean forward though. Besides the form stuff, Alex Huynh lacks power. PRC Wushu is all about speed with no power. I don’t have enough of the form on hand to judge it point by point. The stance is glaringly PRC Wushu though. I also agree with everything Flying Monkey said about Alex Huynh. Would you like me to answer anything else Judge Pen?
By the way,
Congratulations on the baby.
Do you have a name yet?