I don't think it's enough, if the student isn't sure he's ready. Especially when ranking that high. There are several other considerations regarding this issue in addition to the ones previously pointed out: 1. How can you see and evaluate yourself more objectively then your teacher? If the thrust had to do with a questionable moral issue, then you must use your judgement first. 2. If you can not thrust your teachers evaluation of your skill, he may not be fit to teach you. 3. If you can not thrust your teachers evaluation, how can you expect your students to thrust your evaluation of them? That is all true. But if the student doubts whether he's ready, and I mean seriously doubts it, then he's not ready. Teacher's opinion on the techniques is undisputed, but when testing for a black belt one should be able to view his own technique, so that he may himself tell whether it's good or bad. Not everything ofcourse.