Bands are random allocation within the bands and overseen by an independent adjudicator so doubt any truth there.
From what I can see from having a DD in Y10...
Huge emphasis on English, Maths and Science - by Y11 there are 6 hours a week of each.
Choosing options in Y8 and starting them in Y9 with a pre-GCSE prep year so the groundwork is laid before starting the GCSE courses. Good choice of options, SEN kids can drop languages or humanities after discussion with school, BTECs available as well as GCSE and they will facilitate you taking extra subjects if you are keen.
Music scholars have to take GCSE music (so they have enough for 3 separate classes as a result), Sports scholars have to take PE.
They set for pretty much every subject - but you are not stuck if it's not quite working.
Huge importance on being in the right set. DD is good at maths - once she's understood the concepts. She's on the slow side at that part, but once it's done then she's actually pretty good at maths. School picked it up really early on and tried 4 different sets before finding the right teacher, pace and peer combo. Now one of DD's favourite subjects.
They run Saturday schools and after-school groups for those who are behind in GCSE years, and teachers are really amazing at providing extra help - DD did an hour 1:1 after school last week as she was struggling with something for an exam she's taking outside school.
Art department picks up on talent in Y7 - art scholarships available with trips and extra tuition. Same for maths - loads of extra sessions for maths scholars, trips, olympiads etc. Music department run before school music theory classes, lunchtime dyslexic musicians sessions and huge number of ensembles, choirs etc.
The staff will also be on the phone to parents if there's a problem.