Performance art from who's perspective, yours?
Well, clearly, since it was me posting that.
Seriously, though, my point is that when we judge kata, people are going to start adjusting the kata for what the judges award. That means they're performing to the judges, rather than using the kata for its (assumed) original purpose. Again, I don't have a problem with that - we just need to be aware of the affect that can have on the kata. Those effects are not universally bad.
I was referring to wider differences than within TKD. If we look at TKD, Wado, Kyokushin, and maybe even throw in some CMA, we start to see differences that are fundamental. So, we get back to the differences in stance, timing, and flow. I really don't understand how someone can judge a style they don't know as well as they judge a style they do know. I suspect this sometimes goes in favor of the style they know (they see what they're looking for more often) and sometimes doesn't (they are better able to see the errors in their own style). And when performing to judges from different styles, competitors will be less constrained by the actual purpose of the kata (since it will be less-understood by some judges) and some of those who figure it out will adjust their kata to get better scores. Those adjustments are why I refer to it as performance art. And, again, I don't have a problem with using kata for that purpose - I'm not using it as a derogatory term, at all.The competitor may have a completely different viewpoint. I have worked out in every TKD system I am aware of state side. It is remarkable how different, and in common most are. I find this true of the other style schools I have worked out at. A lot of my experience with specific styles is limited, training while traveling for work. But, for the most part, there are commonalities across styles. Even in TKD some schools kick high and some schools kick really high. Emphasis to the point that I sometimes ask why? Then I have to step back and try to find the "why" in other things they are doing and usually find there is some method to their madness. Typically, the people being pushed to the extremes, in kicks for example, are the ones with some naturally ability to do really high kicks. Usually this is done as a way to motivate and keep a person engaged and involved. If it is never taught where/how/when/why to kick (or punch or whatever) then the school or instructor(s) are doing a dis-service.
So when I judge a form or style I am not intimate with I try to evaluate the effectiveness of individual moves, not in a preconceived idea of how the move should be done but whether it would work. Then you start adding in the fundamentals like balance and timing, etc...