You hear this everywhere, repeated in Novels, quoted in movies, etc. Its just one of those things everyone assumes. The whole "These barbarians are incredible warriors, if only they were more organised they would be unbeatable".

Now i was pondering over this at work tonight, and my train of thought strayed towards them being so barbaric as the key to their military prowess. If you sent in a few centurions etc and banged them into shape and a disciplined force, would they lose that inhuman single combat driven fighting skill and just become another standard army? Or would a Roman Legion fitted out with mad Celts with crazy hair and woad designs truly be unbeatable?

I guess im not really asking a specific question as such, just... If the celts did evolve and did form a standardised military training procedure, would they lose their ... sheer ferocity and courage that is typical of Celts?