There are two main methods of transmitting and training Taijiquan: one is the "trunk" method and the other is the "leaves & branches" method. The Yang family were the first known Taijiquan masters to make a living by teaching Taijiquan. They used the "trunk" method for some students and the "leaves & branches" method for others. The "trunk" method requires great effort and commitment in order to have an effect, and has little if any fun or enjoyment in the learning process. Only a person who possesses natural talent, tenacity and a deep commitment to Taijiquan is willing to accept this kind of training. The "trunk" method was used by past martial artists who needed to hone their skill in a limited time to defend home and country. They did not have the luxury of time and indulgence. Today the common method is the "leaves & branches" method. This method does not require very hard practice before yielding the first results. The sense of success and accomplishment is reinforced by the many branches and beautiful foliage - unlike the trunk where there's only the thick body and bark.
However, all is not lost in the "leaves and branches" method. Sometimes a discerning person recognises that establishing the trunk is a prerequisite for the branches and leaves to survive and to continue to be beautiful and robust. This is considered a roundabout and longer route. Sometimes the significance never becomes apparent and the trunk never reaches its full potential or is rendered useless and discarded.