Hi Jeff,
San Ti is practiced equally on both sides. So in other words, you can mirror Bruce’s movements or not, just do what is easier for you since you’ll also be doing the same thing on the opposite side anyway. The transition from one San Ti posture to the opposite side is different than beginning from scratch where the heels are together, but to the best of my knowledge, you can begin with either side. One of the guys who does more Hsing-I may be able to offer more on this.
If memory serves, Bruce mentioned at that training that you typically do 9 breaths (or multiples of 9) and then switch. I haven’t watched the whole DVD set all the way through yet, but I’m guessing there are probably some practice guidelines toward the end.
Paul