philippe willaume

Hello chris
I believe you understood that my tack was to show the relation with the sword and open hand not to say that is the best way to fight empty handed.
And I understand that you propose that it is not really applicable. You have a very valid point but you have as well a wrong assumption.

You see coming close with headlock, body lock, arm lock or throw is a very valid way of fencing (i.e. fighting with using weapons).
In fact all 15th century treatise I know of, consider getting close and wrestling a integral part of using a weapon and the manuals tells how to deal with it or to get to, with and without armour on foot and on horse.
Basically having a weapon does not prohibit close contact wrestling at all.
Fighting with a weapon is full of taking short cut and taking corners even accepting a slice or a small cut to the hand (or a even a thrust through the tight is you practise Scottish small sword……).
I understand that wrestling when both weapons have is not that common in koryu. So other than the body variation of the kumitachi it is quite hard to be exposed to that in aikido or in JMA in general (I think it exist ion some koryu, the bit we do in kumitachi has to come from somewhere).

So this is really where my disagreement why you analysis lay, however on the same vein you as making a very good point.

As you said specialised open hand fighting will have that built in the same way fencing as it regarding fencing. And so if you take fencing approach to open hand you will not have that or at least to the same extend.
One could argue that it is possible to optimise the open hand side of a sword based (and I think that it is what aikido is). But I would agree with you in saying that it can not really be optimised to extend of a dedicated hand to hand method designed for facing hand to hands.
That being said, the sword base hand method can be made good enough.

phil