Now I'm confused!! Have you changed your username Alaska?
I was in communication with my ds's school for a number of weeks over the PP. At the time, it didn't have a policy published online and it has a 50% gap between the achievement (A*-C) of the average and those on PP. I delved into the financial records and discovered that the money was disappearing into a big pot, along with money to replace EMA for Sixth Formers. The school started to panic when Wilshaw threatened to remove the "Outstanding" rating from schools with a big achievement gap.
I still feel slightly ambivalent about PP and I think there's a lot of misunderstanding. The school is awarded the money on the basis of the number of eligible pupils, but it does not have to spend the money on those individual pupils. As somebody mentioned previously, the tracking is all-important. I believe the question should be whether an individual pupil's achievement is being affected by lack of money (the services children are slightly different). If, for example, pupils are expected to work on computers at home and a significant number of pupils don't have computers at home (or even a quiet place to do homework), the school could legitimately pay for somebody to run a homework club. The club wouldn't be restricted to those on PP, but most pupils, given the choice, would probably prefer to do their homework at home.
Ofsted and others have published loads of advice on the use of the PP, including one document (which I can't find at the moment) about the impact and cost effectiveness of various interventions. If I can find the link, I'll post it. I remember that one-to-one tuition was considered to be very effective, but also very expensive.
I must admit that I find it ironic that a government, which supposedly dislikes the "Big Brother" attitude of Labour, takes away money from parents' benefits and gives it to schools to decide how it's spent.