Quick rant...
Bagua is a great art--it needs no defense. But I am tired of hearing so many bagua people--the good, the bad, and the ugly--say that bagua has both Yin AND Yang, hard AND soft, UNLIKE Tai Chi. The symbol for the concept of Tai Chi (the Tai Chi Tu) IS the ubiquitous yin/yang symbol, showing equal, opposing, but harmonious yin and yang as the great principle of the universe. Why use this name to refer to a style if it is based only on yin? And further, a style of only yin/soft principle, training, and techinque would be out of balance, ineffective, and ridiculous.
Tai Chi Chuan that is not balanced in yin and yang is not, by definition, Tai Chi. And while the Bagua trigrams are an exploration of the changes between yin and yang, this does not mean that bagua has cornered the market.
k, I feel better--thanks for the forum to vent