In this video we look at the bunkai of the opening moment of Pinan Nidan. The footage was filmed at a seminar I taught in Wales in 2014. I see the motion as an escape when the arms are pinned from the rear. The “dropping hand” rips the one of the enemy’s fingers back, up and over (only partially done in the demonstrations for obvious reasons!). That will free the grip. The “pulling hand” delivers an elbow to the rear; and the assumption of the stance will help ensure that the elbow will hit the enemy on the vulnerable areas that exist on the centre line.
The inspiration for this application comes from a photograph of Choki Motobu also escaping from a grip to the rear. The similarity of Motobu’s position and the opening move of the kata lead to me concluding that something similar may very well be going on. The Shotokan version of the kata is a little different because it begins with a gedan barai as opposed to a dropping fist. Valid applications certainly exist for the Shotokan version (see my DVDs), but this particular one would not apply.
All the best,
PS The YouTube link can be found HERE