Just SAY ... All the technique taught in traditional systems work.
And, SAY ... we accept that pretty much anything CAN work given the right circumstances - My sword teacher escaped once from a multiple attacker situation with a blade made from the foil in his cigarette packet.
And SAY ... that pretty much anything WILL fail at the wrong moment, at the wrong range, in the wrong circumstances - For instance any strike thrown from too far away, or lock put on badly etc etc.
And SAY ... we accept that anatomy, physiology, and the laws of physics exist.
Instead of arguing eternally about what technique 'would work', perhaps the more interesting question to ask is - In what circumstances is this technique worthy?
Is it only if you have the luxury of numbers and surprise? Is it if they rush you with their sword held overhead? If you have a wall behind you? If they are much taller than you? If they grab you above the elbows? If they try to sweep you from the left? Why?
When WOULD it work? Is it dependent on relative size? Amount of space? Teamwork? Relative geometry?
Perhaps the key lies in examining the principles behind the techniques?
Perhaps it's worth looking at WHY things work instead of IF they work,
and how often those perfect circumstances come about in the field in
which you choose to play.
I would contend that every successful technique happens because of a gift. Either one handed to you, or from an offer YOU made that cannot be refused.
AND when you happen to be in just the right place and at just the right time to take advantage of it. Sometimes effortlessly and in one move. Sometimes not, and with a bit more adaption required as the situation changes.
My teacher got away because it was dark and he fooled his attackers into thinking he had a blade, something they were not expecting. The hesitation he caused gave him enough time to get to his car and escape, but would this work in different circumstances?
Is it worth teaching as a technique to actually practice? Probably not.
And how about a nice palm heel to an open chin? It has a high probability of doing damage, perhaps causing a K.O. But only if you can actually land the shot.
Is it worth teaching? Absolutely. But how about as part of a sword curriculum where there are more immediate options at hand using the weapon you are carrying?
How do you choose what is worthy in your own, personal, context and what is not?
Turns out, that to say that 'everything works' is pretty much as true as saying 'nothing works'.
WHY? and WHEN? Possibly the two most useful questions to ask when sorting the worthy from the not so much.