Each candidate does Palgwe Chil and Pal no count, free fights at least three different people, and does a break that they feel represents their best technique. We don't make them run through every form they ever learned because it is unnecessary. Red belt forms should represent your cumulative technique up to that point.
Coming into the discussion late, and not a TKDer myself, but this comment by YoungMan was made a couple times here, and I wanted to comment on it.
Personally, I think it can be a good idea to test the full system, because I think a lot of people tend to focus on the newer material and put the older material on the back burner. In my opinion, learning a martial system is cumulative. New material, while often based on and built upon earlier material, does not replace that earlier material. Instead, it should ALL be a part of regular practice. But sometimes people become too focused on the new stuff and forget to keep up with the earlier stuff. So the earlier forms may become sloppy or rusty, or, worse case, be forgotten.
If someone cannot competently demonstrate all the material that they have learned so far, then I might question their rank. After all, the rank is an indicator both of skill and having a body of knowledge. If the knowledge is leaking away, then is the rank merited? So testing it all is a way of making sure the student is keeping up with it all.
If the curriculum is very large and this would require an unreasonably long test, then perhaps not everything needs to be tested. Instead, there could be a random selection of things that the testers want to see, but they can choose anything from the entire curriculum and not just the most recent material. This way, the candidate at least has to be prepared to do anything, because he won't know ahead of time exactly what will be called.
Anyway, this is just my thoughts on it. I kind of feel that if the formality of a test is to be done, then do it all and make the candidate work hard for it. I don't know that I agree with a multi-day test, but for some people that works. But testing the entire curriculum, and making it last at least a few hours seems reasonable to me. Force the candidate to show his heart and spirit and committment.
AFter all, by the time someone reaches shodan, he should have a genuine personal committment to training. He shouldn't need the teacher to push him to train. And part of this personal committment means being mature enough to recognize the value in the complete system.
On the other hand, Sukerkin has raised another valid point, that being that some schools don't test at all, Instead, they are constantly testing the student daily. When they see the skill and committment and body of knowledge necessary shown daily, then the rank is simply given. This makes a lot of sense to me, and perhaps in a perfect world this would be the best way to do it. I think this kind of thing works best with a small group, where the teacher really works closely with every student and therefore knows exactly where the student is in his developement. In a larger school with lots of students, it may be more difficult for the teacher to keep such close tabs on a student's progress.
anyway, just my thoughts here...