Seeker
You say the high school is good, that your son is bright and that you are achingly middle-class. You also state that you are quite sure he will do well at the high school where the range of subjects offered is not inferior to the grammar except there's no Latin. You also state a bit tetchily that this is not a disaster for your son or you and that of course you are not obsessing about this in RL (as that would be silly).
Apart from snidey comments from strangers about pass / fail, what exactly is the problem?
Yes, we all get that you are against grammars, sorting of kids into sheep and goats at 11 and the negativity that surrounds perceived failure. These are high principles which you can promote via your MP and local council, but really have no relevance to your son because as you keep telling us he is going to do fine.
So, why keep on postig about your son's specific case when actually you really the grammar system won't affect your son academically, only possibly on a self esteem level, and you have had plenty of people on this thread tell you that you need to buck up because your attitude is probably more detrimental to his self esteem than a random off the cuff comment from an unknown teacher.
I would have enormous sympathy for you if the high school was in special measures, with discipline issues, absenteeism, drug taking, pregnancy and inter-school violence rife. And if the high school only offered BTecs in Hotel Management and Media Studies.
That would be a scandal.
And remember that for many, many of the disadvantaged around the country, that is the reality and they have no options.
You need to get over the self esteem stuff and move on. Fight the good fight for FSM kids at a political level without using your son as a case study as he really undermines, rather than strengthens, your argument.