Re: The GREAT kata debate
y'all covered it pretty well, so i'll take a viewpoint and address briefly from there:
neuropsychology: we learn by strengthening connections between adjacent neurons; this has been demonstrated experimentally. repetition creates stronger connections and thus more likelihood that certain neural links will be preferred. we call a correct response 'good training' and continuing to repeat old mistakes as 'bad habits'.
the limbic portion of the brain can not speak, nor can it program a computer. it can distill the rules out of complex systems that would leave the neocortex stammering. what we call 'natural' response in a life threatening situation is action of the limbic brain, that the neocortex may only be dimly aware of. kata strengthens certain associations, hopefully good balance, etc.
if your life is threatened you have no time for kata - you do have time to respond naturally - limbically.
you may do one move from the kata - then run like hell. you intuitively apply what you have gained through study - or you die. of course, only the survivors of life threatening situations are around to advise us!
read 'A General Theory of Love' by Fari Amini for more on neuropsychology.