Old Soldier, Tom L, this is the reference for Robert W. Smith that I was referring to previously

Martial Musings

Smith lists some techniques in the Fairbairn syllabus that he thinks just won't work, they may not be in the system that was linked previously

1) a one armed choke...a two handed straight choke is almost useless, I can't see a one handed choke having any effectivness

2) The back breaker, lifting an opponent up an breaking his back over the knee, unless you are an Olympic class power lifter I can't see that working

3) Match box versus gun...a soldier is held at gun point, he grabs a matchbox clenches his fist around it and slams the enemy in the head. Fairbairn claims a two to one probability of knocking your opponent out. I think you will break your hand and then be shot if you try this one

4) an odd hip throw where by standing face to face with an opponent you step behind him and throw him over your hip...Smith is correct, this is an ineffective technique, you would be better off using the judo throw o-soto-gari, it would be faster and take a lot less strength.

I have to add , I just think these techniques are ineffective, a friend of mine teaches WW2 combatives and has appeared on documentaries on Camp X, a lot of it is good stuff.