I do get a little nervous while my DYS6 is testing, but I've come to recognize that I'm simply projecting my own perfectionist test-taking stresses on the situation. (I took bar exams in 4 different states, and threw up before every one of them. Calm, I'm not!) I also remind myself that I need to check my ego, since I suspect that a lot of parental stress is tied to our own pride over their achievements.
My best advice is to use the testing as an information-gatherer, but not to read too much into the scores either way. I want to jump through the computer at parents who keep retesting their kids or sign them up for all sorts of prep tests. Why?!? Is that really in their best interests, or just our desire to see them ace the tests? Even if they have an off afternoon, it doesn't change who they are. If they are truly different from the rest of their school children, the teachers can see that more from the classroom time than a test, anyhow. Unfortunately, though, we've discovered that even if they understand and support the fact that your child is PG, there simply isn't enough they can do anyhow.
I think it's easy, too, to get competitive and forget to put these tests in context. Most of us parents here are probably HG too, and I know my DH and I never had access to these tests, online classes and communities, etc. Nonetheless, I'd like to believe that most of us have led happy successful lives. I do believe some testing helps open doors, but it also leads to disappointments or new worries if the results aren't what you want. At least....this is what I keep telling myself to try and calm my own fears when my children test.

Nowwhat & cricket, I like your taekwondo stories! It's fun and exciting to see them bring their concepts together! We must have a lot of taekwondo kids here. Mine is one, too! (He just got his lower green last week.)