Re: Sunadomari Quote - Opinions Please
I agree. Tenkan as it is traditionally practiced is pretty much useless if applied the way it is practiced in its "kata" form. However, the way I look at tenkan is to change the angle of insertion (entry) or angle of retreat (in order to reinsert). How much of a tenkan is needed depends largely on what angle is required - it need not be a full 180 degree turn. Tenkan is only a small part of the larger picture of ashi sabaki and tai sabaki.
BTW, aikido isn't the only martial art that uses a pivot (of varying degrees) to effect tai sabaki.
In terms of using it as an ashi or tai sabaki response to a boxer or kickboxer, the usual disclaimers apply - whatever works in that particular situation, I guess.
In terms of evolution, varying things, dropping things, or adding to - I guess as long as the principles are adhered to, then the "techniques" themself are of no consequence.