Fair enough - our school was 'good' and getting decent results when mine started. They went 'inadequate' for a while but are back to 'good' now. We did consider moving DD2 but she wanted to stay and will do fine regardless.
If the school is working for you teen within those rules, then its not a problem - I suspect it wouldn't work so well for a lot of SEN children though.
The two things I would keep an eye on at a school like that is whether there seems to be a high rate of self-harm and MH issues and also off rolling in years 10 and 11.
One of the (all girls) schools we considered for DD2 had great results and Ofsted reports and was quite strict (although not as strict as yours), but when we looked into it, there was a lot of anecdotal evidence from parents and former pupils about very high levels of self-harm and really strong evidence that they were off-rolling pupils who might affect their results in year 10 and 11.
Ofsted came down hard on it, but schools who want to can still game the system.
I am surprised they get the results they do if kids can't ask questions about things they don't understand. Also, how do they teach critical thinking skills if they can't discuss and debate - especially in history and English Lit?
I know the current curriculum is set up for learning by rote and to minimise critical thinking, but even so!
If the curriculum changes back to focusing on deeper understanding and critical thinking (which hopefully it will), I suspect their results will dip unless they lighten up!