Re: Pop quiz, hot shot
Our school has done the "surprise you just tested" thing before, only with mudansha though. They try to make yudansha tests relatively nerve wracking.
A teacher of mine was testing for godan (not usually a physical test for this) when a teacher from Japan was in town (I think it was Terada Sensei). Two days before the test she was informed the testing requirements she had been studying changed significantly, but she still passed (and did really well). This was for a Yoshinkan test, so the test was rather detailed and specific about the things required in it (for example the 1st kyu testing requirements are two pages long).