Xue Sheng
All weight is underside
i mean qi's training is totally different training, such as qi gong or dao yin(导引). in taiji's training, external movement will lead your breath or qi on the right way. my master always say: when you are thinking of qi, you lose it.
in taiji, there is a saying:there is your mind, there is qi(意到气到).i suggest taiji practitioners pay more attention to the movement than to the qi.
I fully believe that for a beginner it is much more important to worry about form and posture and not so much about qi (or breathing) becuase they will follow as ones form improves and as one gets more comfortable in that form.
However in the flavor of Yang style I train, as it comes form Tung Ying Chieh (董英杰