@mantrama wow, this sounds just so wrong. How do they expect to maintain this kind of level once they are in the school!? I honestly think, if you need to study this much to get into a certain school, it is probably not the school for you! It is possible to pass the exam without such a crazy amount of prep.
We did not try for SPGS, but passed the exams for all schools applied for (G&L, Putney and Emanuel - also applied to FHSS). My dd is from a state school and only started prep from end of year 5 (end of May) because we did not realize she would do the 11+ route. She did not do crazy amounts and even did 3 weeks of no studying during the summer holiday! (not by my choice, she was abroad with her father and he would not get her to do anything). She kept all her activities during the 11+ This means she did something 6 days a week, and weekends two activities daily (this was all by her choice, as I thought she should cut one or two out for a term, but no, she did not want to). I would say she had a relaxed attitude to studying. If I had to drill her constantly, I would wonder if these are the right schools for her. It is possible to get in without doing a crazy amount of prep.
But I do think many get scared when reading the types of post you just wrote and feel they need to live up to the same standards of studying. I am sure there are loads of girls that do this kind of schedule. Makes me sad for the dc, who seem to miss out on their childhood!