This was the advice given to me by a child learning practitioner (not a teacher but a specialist who works in schools). They said to "always defer if you can, even if you think your summerborn could cope fine... Better to be one of the eldest than one of the youngest".
My DC2 is a summerborn (not school age just yet though) and the above comments are playing on my mind.
We can afford the extra year of childcare, and having seen my nephew struggle as a summerborn, I must admit it's something I'm considering. DC2 is a bright little thing if I do say so myself! so I am imagining that we would be doing it purely because we could rather than because we'd need to. Education is very important to me and whilst I don't necessarily want DC to be top of the class, I want to give them the best possible start in life. It feels like deferring would do that, whereas not deferring would possibly make me doubt/worry/question whether I'd done the wrong thing.
Lifestyle wise not deferring makes things easier having less of a school year gap between the DC. And I imagine they will be closer if there is a smaller gap... But... But.... But... DC might be "fine" if we don't defer, but "amazing" if we did.
Can deferring be a bad thing??