18 Shaolin techniques and self defence application

It has many purposes: to make your hands closer to the opponent's lower body, to make your body shrunk against high level attacks, to be able to make a displacement near the opponent's body in a safer position, to lower whole body weight as a support for down-going pressures and attacks, to make it possible to rotate your trunk while raising up which has many applications,...

The T stance is a transient stance, not a steady one, i.e., it is used while a transition from a side to side, with a leg on sole supporting the whole body and the other leg proceeding the transition.
The Chicken stance lowers your body in order to do a maneuver at lower heights. Because of one foot being in front of the other, this stance has a very good balance and it is appropriate before advancing, at which one foot can take a firm step forward with the rare leg supporting the movement.