I got done quite bad back in the 90's, got 4 big wounds on back of my head. They did my ribs too, and first thing that happened when i came to was i got fucking hiccups, as been boozing on cider earlier. Never had pain like it, everytime i went "hic" it was sheer agony.
As for what London mobs carried the most blades, i would say Spurs. Under-fives used to carry, but seldom use, was more into threatening to do it. Arsenal had a few slashers, but have to agree that chelsea never were into it to my knowledge. The Reading incident aside.
Spurs lads were fuckers away from football, as in if you were drinking in their manor, or running into them at Covent garden etc.