Two more futile years?

I know what they are trying to do with education with the proposal to raise leaving age to 18 but I'm troubled by the idea, and this article pretty well articulates my concerns. Here's a quote that encapsulates much of it.

Accurate data on literacy and numeracy (even when analysed by such statistical wizards as Claus Moser) is pretty elusive. Is it 20% of the UK population that is functionally illiterate, or 10%? But bet, with a dismal certainty, that most of the problem teenagers are also the children who never quite mastered reading or writing to begin with - the hard core of the 20% of functional illiterates who came out of junior school at 11. Bet that they drop out at 16 for a desolate reason. Bet that the failures in GCSE maths and English that were revealed by making them mandatory in last week's school league tables are reflected worst of all among those with nothing to do and nowhere hopeful to go.
Do you solve that problem by adding two more years of the same? You haven't solved truancy or illiteracy or breathed new life into further education. You haven't (see asylum seeking) got either the time or the resolve to chase 17-year-olds who bunk out of apprenticeships.

The rest of it's worth pondering too.
Peter Preston: Two more futile years | Schools | EducationGuardian.co.uk:Filed in: education, compulsory, UK, post-16