twiggles, a lot of us are not school teachers
I am a university lecturer and have absolutely no axe to grind: all my teaching is judged on student feedback which is recorded and has an impact on my career; I have no problem with that whatsoever.
however, there are two factors here:
a) school teachers already are monitored closely and parents do have the right to feedback- I have used it many times myself as a parent
b) when monitoring is done in any situation, questions need to be formulated so as to bring out constructive criticism, and in this particular case due care needs to be taken to the fact that some answers may not be guided by a genuine desire to improve the learning situation
unlike customers at a bank or students at a university, school children generally do not have a choice about attending school, and some may have negative attitudes that are not to do with the actual quality of the teaching
there are pupils (and parents) who actively dislike the idea of learning and whose rating of a teacher will be in an inverse proportion to how much learning goes on in her class
in my ds' case the definition of a bad teacher is one who forces him to work- he doesn't like it and is too immature to understand why it is good for him
if I listened to his opinions of which teachers are unfair or incompetent, my black list would contain all the most efficient teachers in the school