Dear Uncle Dixer: Feng Shui Audit energies are real enough. But we have to ask the pertinent question and not give in to compliance simply because it is tradition. This is about the Three Killings (San Sha). Why is it that we have to face it, although this is not necessary, but this not having your back against it really piques my mind to no end.
For a fact, the 3 killings comes from any of the 3 combinations/branch 3 unity, Si-Chou and you as the year branch. This is about the maturity of the Metal Element. Then from you towards its opposition Mao, we have the San Sha which energy from you flows over to the two signs besides it. Now how is it that not having your back has anything to do with being the victims of San Sha?
I don’t want this to be taken metaphorically either. So with these facts given, can we go to the roots of the San Sha? (I am of the opinion that having a pair of Qi Lin (Kirin) must have something to do with taking on the energy. This is expressed as instead of you having to face the San Sha. You have the Kirin to do it for you.)
Answer: The 3-Killing or San Sha is one of the collections of Shen-Sha in Feng Shui. Shen-Sha can be literally translated as the “Sha of the Spirits”. But in Chinese thinking, a spirit is not the same as we understood it in the West. A spirit comes from correlative thinking based, in this case, on the Stems and Branches as you mentioned, and Sha refers to something out of balance. It “kills” or “sha” the potential for things to grow and multiply.
Not having your back to the 3-Killing is associated with the idea of not turning your back when some directions in a year is out of balance, but to overcome it instead. You don’t have to fight it directly yourself, you could use something like a Kirin as a spirit-symbol to do it for you. In some way, your explanation of having a pair of Kirin facing the 3-Killing do make some sense. Note that it is a pair of Kirin to represent the Yin and Yang, to transform what is undesirable to be desirable.