Researching the form Parting the Wild Horse’s Mane I found this website: Yang Family Tai Chi Discussion Board, and came away with this fascinating interpretation.
Dr. Yang Jwing Ming also translates this as: “Wild Horse Parts Its Mane.” And he explains the reason for this translation like this:
A horse is a powerful animal, and a wild horse is particularly forceful and vigorous. The name of this form gives the image of a horse tossing its head vigorously and shaking its mane. The word “Shear 分” here is used because when you do this form you “tear” your hands apart as you turn your body. The motion is continuous, extended and powerful. It is a long Jin that can rend the opponent off his feet.
(From his book “Tai Chi Chuan, Classical Yang Style)
This is the clearest video I could find that shows the form — it’s up to us to imagine the power of the horse parting its mane.
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