Real fights,knife attacks and multiple opponents should be seen as ambushes and should be delt with as such. GET OFF LINE AND LAY DOWN SUPERIOR FIRE POWER. Train to be aware and at the first indication of an attack MOVE and go from aware to 100% all out attack. SAS surprise aggresssion and sustain. DO NOT "compete" it is near impossible to block numerous attacks. You MUST take the intiative and ATTACK AT ALL TIMES with no concern for defence once you have initiated the attack. ALL training should be done as though a knife is involved. This shall lead you to discard many techniques and concentrate on attitude,principles and explosive pragmatic action. If I am close enough and circumstances dictated that I must pass between two opponents I would take one of them out or crash right over him.I would still much prefare to train so as to keep one between me and the other. And NEVER turn your back or lose sight of the danger even for an instant. Incedently walls make excellent weapons. Crash him into it drive him into it to negate his mobility. All of the above is based on working in deprived areas of Glasgow.The martial art part boils down to attitude awareness general toughness. Even if the technique is unsophistocated..it is the one with the strongest decisive attitude that has the better chance.