Regardless of whether the tournament were a truly traditional one, or a fully open one, it comes down to the quality of technique, and how good the fundamentals really are.
Some schools may use modified kata sequences, and if that's the way they do it, I cannot fault them for performing the sequence that they were taught.
However, where I can fault someone, is if they try to put a premium on flashiness at the expense of good fundamental technique. If I see someone's hip levels bouncing up and down, while trying to do a traditional kata, regardless of whether or not they have thrown in aerial techniques or techniques from other kata, then I'm going to deduct points.
If I see someone coming up on the ball of his plant foot when throwing a kick, I'm going to deduct points, regardless of what the tournament may be.
As a *generalization* of what I've seen at tournaments, people who try to spice things up by catering to the flashiness at the expense of solid technique, really have sloppy kata, and I have absolutely no hesitation when it comes to deducting from their scores and / or voting for the other guy (flag system).
On the other side of the coin, I look at traditional Karate competitors who have won championships, such as Luca Valdesi, and see the modifications he makes to his kata to make it look more flashy.
In those cases, I'm not impressed by such modifications. For example, in his kata Gankaku, he uses a high side thrust kick, instead of the snapping side kick that normally goes to the mid-level. I honestly believe that he shouldn't be doing that at the traditional competitions, since he's obviously good enough that he could win by doing the kata the way it's supposed to be done. I can't argue with the world level referees, since they've seen his excellent techniques.
Where I especially get irritated, though, is when other people try to copy his methods, and do so at the expense of good technique, thinking that his way must be right because he wins...