I sent DD1 off to college hundreds of miles from home when she was 18, and she actually never had to lift a finger to do anything but her own laundry. Meals were included in her fees. She rented a room for herself last summer because it was close to her job and never came home at all. After a brief panic when she realised she could cook but couldn't imagine what to buy or how to plan her meals, I sent her instructions and a shopping list. Bingo she was set. Independence accomplished in the space of two days. DS will hopefully head off this autumn and will be in the same position in college, with room and board provided. Both could manage to cook a bit and do their own laundry before they left home. DD1 can now keep all the balls in the air at the same time work/school full time, shop, cook (she entertained er friends a few times during the summer), eat, clean, do laundry. She wouldn't have learned any of that at boarding school. But she did learn it at home and there's no reason why a parent should be doing laundry or taking care of money for an able bodied teenager.
Don't know if students at boarding school are supposed to cook for themselves or do their own laundry, but both of my parents had meals and laundry done for them, and so did my cousins who boarded. They didn't go home at weekends, just at holidays -- mind you that was a while back.
When we talk of independence here, are we talking about 'emotional independence', a reduction of the connection between parents and children as LeQueen suggests? Because I don't think organising your own social life and the other aspects of boarding school life that students have to take care of for themselves constitute taking care of themselves in the physical sense.
Candleshoe and AlbertCamus -- your observations about drugs and drinking ring a bell with me. A friend I went to school with to 15 attended an Irish boarding school in the Dublin area as her parents were abroad, and her stories of the goings on there (and this was way back in the late 70s and early 80s) would have put even the edgy crowd at my school to shame. My cousins emerged without any major addictions from their boarding school but plenty of their classmates fell by the wayside.
BTW WriterofDreams, the boarding schools I mention are all in Ireland. Some Irish families do the boarding school thing through the generations. For my dad's family, it stopped with his brothers and sisters.
I did the 5 am starts and the weekends schlepping children hours in both directions and still do. The DCs have swum, done water polo, badminton and football, and drama too. None of the DCs so far have suffered at all from their early starts. DD1 in particular was an outstanding student. One reason (apart from the thought that she was a bit young to be leaving home) not to send her to the boarding school we were considering was that she wanted to participate in sports at a school that was competitive and the boarding school was essentially for stereotypically geeky and nerdy students, fielding teams that no-one took seriously.
The chorister thing makes me think of Chinese gymnasts. Those little girls are has-beens at a young age. You're not guaranteed a singing voice past puberty if you're a boy. How is it a skill for life? Actually, having seen a friend of DD3's do modelling (print and screen) from about age 6, I think it teaches a lot to children. She is a very self-possessed young lady at age 12, with a lot of confidence.