I don't know the answer to your question, but I want to support you in what you say about potty training. Many children are perfectly capable of being trained at that age. I think it is bizarre to suggest (as some do) that all children have an innate developmental stage where they suddenly go from incontinent to able to hold wees and poos until they get to a toilet, fully clothed. It is not supported by evidence from other cultures as you say. Some children can and do do this, but often at quite an older age 3+.
My oldest two were both out of nappies in the day by 22 months, and dry at night before 2.5 yrs (latter a fluke, we did nothing). One of them was doing all poos in potty at 10 months. Started as catching poos that came at a regular time of day, and became habit, then awareness before 18 months.
My third was actively resistant to potty training, and I was less motivated to encourage, so ended up leaving it until over 2 yrs. it was much harder.... Maybe it would have been anyway, who knows. Different temperament of child. Was still out of nappies by day by 2.5 and dry at night soon afterwards. With all three poos far far easier than wees.
My youngest at 17 months does all poos on potty, and has since about 14 months. Same method as the one who did it at 10 months. It has not been a huge effort, just paying attention to straining, talking about it, and whipping off nappy and sitting on potty straight away. The baby has to be receptive, and I'd say you need the right frame of mind and plenty of time too. No idea when wees will follow, not yet! But then, with the others it has always just been a case so seizing the chance when the time 'seemed' right. We don't have a science to it in this house, and I haven't read any books.
We found bare bum and potty nearby, followed by trousers with no pants, and then eventually pants and trousers worked best once trying to sort wees out. Once they were ready the progression from bare to fully clothed and vaguely reliable took 2-5 weeks in total. It was easier with the oldest when we could stay at home all day. With one so young, you may well still need to take them to the loo frequently (2hrly) even when trained, as bladder capacity small and easily absorbed in activities! With the younger ones I used reusable training pants for school runs. I have found pull-ups useless. The children treated them just like nappies (which they are). They are marketing to gets parents to buy nappies for longer.
Some argue this is not full training, but to me a clean dry child who only needs to be taken to the loo every 2hrs before they are 2 yrs old is a huge win for both me and them over ongoing nappies. Cheaper, cleaner, drier, more comfy, nicer all round. However, each to their own 
From my own experience I'd say your LO is probably not yet ready to go for wees. I'd suggest keeping taking about it, catching them at convenient times (eg bath)' nappy free time when you can face it. Then, when they show more interest stay home for a week and really focus on it, see how it goes.
I expect you will find your views and mine are not mainstream on MN or in the UK. I find the idea of a magic age of 'readiness' sounds to me like something a nappy manufacturer would use in marketing...