I also had a question about this posture. During the palm thrust, is the focus of the power ("jin" point) in one of the fingertips, the fingers collectively, the center of the tiger's mouth, or the side of tiger's mouth where the index finger is.
I have a vague recollection from a seminar three or four years ago that the palm thrust was aimed at the opponent's throat and that one was striving to make contact with the base of the thumb side of the index finger. As I look at Yang Zhenduo's new Chinese book, however, the application appears to be a thrust to the windpipe, which one brackets with the "v" of the tiger's mouth.
An allied question I have, is whether the fingertips, wrist, and elbow are in line, whether it is the tiger's mouth, wrist, and elbow that line up, or whether it is the index finger side of the tiger's mouth, the wrist, and the elbow that line up.
Lastly, does the point of the strike line up with one's midline or are the left elbow, left hip, left knee, and left foot all lined up?