...but here's my take.
Here's a photograph of my boys' lunches today (I know, I know - it's a long story!)
Ghastly, yes, I agree given my stance. But here's the thing - the time is 8.45PM - night time! That's right - both of them DIDN'T eat their lunches. They both have two rounds of bread with no sugar peanut butter and a scrape of honey or jam every morning, and more often than not their lunch comes home with them. So today my eldest, Thomas fasted from 8am till 5pm - 9 hours and he broke that fast with two eggs and a piece of bacon. Luke went from 8am till 7.30pm (eating at a friends house) 12.5 hours. Both of them are like whippets, don't carry an ounce of fat and have six packs I envy. They fast automatically twice every day (inc. overnight) with no input from me whatsoever and will not eat until properly hungry.
The other take home, and probably the nub of this discourse, is that their baseline insulin is PERMANENTLY low. They burn their carbs, replace glycogen and access their fat utterly effortlessly and cyclically, which eases my conscience somewhat!
There is no question the young (15 &13) can handle carbohydrate far, far better than adults or the old. But the difference with my two is they listen to their bodies - their appetite - and trying and get them to actually finish a meal - well that just doesn't happen, they stop when they feel sated. They are severely restricted on the sugar thing though (and will eat cold broccoli - ugh).