the point i probably flubbed is that ichigeki hissatsu is not an EASILY accesible ideal, but the cumulative effort of years, perhaps decades of the right training. if you want to churn out brawlers, then a system that builds on the body's ability to receive punishment and the reflexes to minimize it of course would be the way to go.
bull-stoppers like mas oyama aside, ichigeki hissatsu doesn't have to be a physical strike. you can take kano jigoro's legendary "yamaarashi" judo throw (by repute one which cannot be countered - there are texts for this but no one since kano has been able to replicate it correctly) and that would be the same thing.
translated loosely, the concept of ichigeki hissatsu doesn't have to be the karate seiken (lit. "standard fist") punch ... it can be any move that can end a confrontation immediately. i don't think there's an inherent emphasis on butt-kicking in it; but the ideal serves to pinpoint that if forced to engage, then the quickest end possible is the optimum solution.
(*peers out of hole*) am i still alive?