Interesting. A few things strike me.
First off, Maddie. When she gets to school undoubtedly she'll be on a G&T or some form of extension programme. She'll so get extra resources directed at her and won't be left to coast as she progresses through junior school. Maddie could be most of our children, if they had that input they could be doing as well academically. Many, IME, don't seem to grasp that. That boy, with the Kumon leader mother, was reading Charlie and the Chocolate Factory at 6 and able to grasp it. Again, many children could I believe with that level of exposure and practice. Again at school he will perhaps be on a G&T programme and so have extra resources coming his way etc. These children are likely to do very well at 7 at 11 and beyond. If they are 3b or 3a at the end of the Y2 - for example - there will undoubtedly be high expectations for 11.
Secondly, Kumon maths. It's an arithmetic tool. It means that children will usually develop speed and accuracy if not the understanding early on. This means a likelihood of top set, top table in infants and juniors. Again a increased chance of a better academic outcome. Speed and accuracy are valued early on, they're noticeable in a large setting, these children stand out and so usually these children have a head start. They will often be seen as brighter.
57% of those surveyed thought their children weren't stretched at primary school - strikes me as a lot. I do feel that children can do more than many realise. Striving for academic rigour, even when children are young, isn't always a bad thing IMO especially when the children have balanced lives and play too.
I thought it was a good point that the overly coached child often felt resentful and alienated from peers who were more intent on playing etc. Made me think perhaps, as the world is going to get much more competitive, whether this will change in the UK in time?