But as to the bolded, from my perspective I'd say the same regarding the OP's actions.Oh, I agree. My wording may have implied something other than I meant. To me, it seems some posters believe the teacher's actions DID shock the conscience. I don't think either of their actions did, although I do think the OP was wrong in how she handled the situation and that it would be in her and her DS's best interest to apologize. And as I said, I think the teacher probably would be better off apologizing for the altercation situation also. But based on what I know from what the OP posted, I do not think the teacher had it out for the DS or actively was harming him throughout the year or during the incident in question. I don't think she needs to apologize for making a split second decision to restrain a violent child. I do think that if it would help the OP get over it, the teacher should apologize though.
Where I differ from Turtledove on this stems from my read of the OP (discussion of restraining techniques not working occurred regularly over months, the issue persisted, and teacher said she was learning about purple as quickly as she could then later acknowledged she had been to busy to train during the year) and what I think Turtledove is reading as a single instance of restraint.
It it were a one-time occurrence, with discussion/agreement on what would work going forward, that might be upsetting, but an emotionally charged discussion would seem counter-productive.
If this was a repeated occurrence, where OP - or anyone - repeatedly raised the matter of the inappropriate and ineffective technique, had that information accepted and was told the teacher was working to learn appropriate techniques - then, wash, lather repeat - I think OP becoming emotional was completely understandable, and rather than make any apology, the most I would suggest OP should do is be appreciative and supportive of current, trained teacher, and pursue productive and complimentary communications with those now involved in administration of the school.