'Also, it's quite typical for people who wait until a bit later - say, 2;6, to report that the initial stages of toilet training took a few days in comparison to the type of training carried out from 18 months to 2 years where parents will frequently time potty sessions very carefully, have lots of accidents to clean up after and forward and backward steps.'
That has simply not been my experience. I've seen so many posters on mumsnet saying they are having problems potty training two, three, and four year olds, and they are getting very stressed out about it because they have the time limit of a child starting school.
The age of potty training has significantly changed over the last 50 years, and I don't believe that is because children are physically less capable now.
Children in the UK are potty trained very late, even compared to other countries within western Europe. Again I don't believe it's because children are physically less capable in the UK.
I think it's because of false believes about potty training. Parents seem to me to be terrified of potty training, terrified of psychologically damaging their child. They seem to wait until some magic moment when their child is suddenly ready. They are looking to tick off a whole list of things that think tell them that their child is ready. They really think that the longer they wait, the easier it will be. And I don't think that is true in many cases.
And I don't see the occasional wee or poo accident as a 'step back' or a failure of potty training; I see it as the child learning about their own body and about what their own body is capable of.