there are many stances involved in developing root, in my opinion, besides the basic horse, bow, twist, cat, kneeling, crane,etc. one of my favorite techniques for rooting is the mud sliding step used in ba gua, this way you are rooted and mobile at the same time.the weight is placed on the rear leg. the weight is not transfered to the lead foot until the body is over it and you are ready to pull the rear leg through. this way it is difficult to be swept, and your movements become more cat like.