Interesting angle that you put forward, your own level of understanding and personal opinion, and good luck with that. There is no shame or underhandedness in testing each others abilities, how else can we learn and improve? As long as it is done with the right mind, constructive and not destructive.
*shrug* I'm too focused on developing my own abilities to really worry about anyone else's. (Except when I'm the person teaching the class.)
As for testing a potential teacher, I've been fortunate enough to study with teachers who are well beyond my ability to actually test them. If you don't feel that testing your teacher would be pointless, perhaps it's time to find another teacher.