There is no doult that children learn best in the early years. However whether children learn best from their parents or nurseries is open to debate.
My feeling is that a baby who is a few weeks/ months old is better off breastfeeding and being with mum than being put in a nursery. I think children benefit from nursery education from about the age of three.
Children with developmental problems need faster intervention than they get now. Its crazy that the waiting lists for speech and language theraphy, audiology or physio in some parts of the country are half the child's life time.
However I think its important that health and education professionals bolster the confidence of parents rather than undermine them by suggesting they are unable to bring up their children properly.
As far as the issue of social mobiltiy, I think its more complex than early education. A lot of it is to do with admission criteria of state schools. There needs to be more social mixing in state schools than there is at present. It would be interesting if all state schools were made to take a similar percentage of kids with special needs and maybe some ablity/ financial banding of parents.
Our local comp does not offer 3 seperate sciences at GCSE. The nearest school which does is over a mile away. However this school is extremely over subscribed. Therefore a child who lives in our street would find it extremely hard to become a doctor however bright or hard working they might be.