Well, before the establishment of karate do, I can think of at least eight tote jutsu versions of Pasai.
Koryu, Guwa, Isshimine, Tawada, Matsumora, Matsumura, Oyadomari and Kyan no Passai.
How many of these have a Dai Sho, Ni or a San version?
Are there any more pre 1922?
What are the post 1922 versions (probably a very long answer?)
Are the different versions different ways of applying the same self defense techniques, or are they what the old masters saw as a better technique and more effective retaliation to an attack?
Let's start on the bunkai for the salutation and the initial move ( low or high covered fist, then a step/fall foward with a augmented inner blck or a augmented hammerfist strike chudan).
There are the applications learnt from Patrick Mc Carthy, firstly where from a frontal bear hug, the good guy strikes the base of the skull of the attacker, the other hand pushes the neck up, then the back hand slides aroud and the fist is formed, and a sharp push is delivered via the knuckles to either the carotid juncture or GB 20.
There was another taught by Mc Carthy, where the attacker ended up huddled over, head between the knees of the defender, arms jammed and wrenched upwards, the defender is in the "hands high" position. How this was achieved I cannot remember.
Mc Carthy taught a third apllication, from a bad armbar. The attacker held the defender in a figure four of sorts, where the arm is tucked under the shouler, other hand on formarm, and the shoulder handlocks onto the forearm grabbing arm. The defender bites the attacker on the back of the tricep (Colon 13 or 14) grabs his locked hand, turns under the armbar and ends up with the attacker on the ground locked up with the hands down low. When the hands are shifted up, the lock is fully applied.
I have worked out some possible applications for Bassai Dai and Bassai Sho. You probably work out which version my Bassai derived from from reading this. I am fairly sure the Bassai Dai is Matsumora, whilst I am unsure of the Bassai Sho.
My Bassai Dai I
To get into the salutation, a defense for a punch is shown. It is similar to lock that may be taught to bouncers and so on. Trapping a straight or circular punch (not an uppercut), by stepping to the inside (risky) or towards the punch, the front hand is used shuto into the nerve complex in the forearm (whatever is avaialable) and the rear hand smaches into the bicep or SI 8. (Since you have probably stepped foward, the hands are now reversed) Quickly, turn away and under the attackr's arm, shifting the rear (front) hand down and form a wristlock/armbar, the attacker shuld be bending down. This is the salutation. The first move is a kick to the face and then the leg locks over the neck. From here, fall foward and wrench the arm from it's socket.
My Bassai Dai II
From a double hand grab (one on either shoulder or lapel), the hands shoot up wrist first, stepping back, (perhaps a groin kick) or striking under the chin, and perform double inner blocks resulting in a double armbar. As the hands come back toward your chest, form the closed fist and strik down or apply pressure to the sternum or use the middle and index finger to poke the throat. If the first move is now performed, it can be a kick to the knee, shifting of balance folled by an augmented hammerfist to the top of skull, or nerve cluster (triple heater).
My Bassai Sho III
From a wrist grab, perfom the opening hadn salutation to apply a wrist lock, (which works on either hand) and deliver a ground kick of kick to knees or LV 10 or so on, and "flex" wristlock and throw them to the ground.
I beleive this is one of the first applications everyone discovers for themselves.
My Bassai Sho I
From an opposite hand wrist grab, palce your other hand on their wrist and begin to apply a finger lock on one of the two sets of fingers. Raise the arm to the high position, knee the attacker in the peroneal nerve and give them a rising/round elbow into Heart - 1. From here, use a Hapkido trip where your body weight is lower then the opponent, and lock shins and push foward (works with the having either leg foward). They should have their leg straightened and fall backwards. From here, apply the lock fully.
That may be a little too elaborate.
My Bassai Sho II
From a two hand grab again, hold down one hand with the arm/shouler it is on, knees to groin, either elbow to chin or thrust into throt and grab trachea, swing arm on up,shift weight, bring both hands together and deliver an augmented knifeand to the neck. A set up strike to the forearm ala knifehand blocks may be possible. If you are coordinated enough, the shift in your body weight not only sets you up for the strike but to land ina manner which bumps the attacker and upsets their balance.