Wow, this has been a really interesting thread with some real gems in it!
I only had a small weight gain from RRARF (approx 4 kgs/9 lbs), but I think that is for a few reasons:
1) Fortunately, my metabolism wasn’t too badly damaged. I had spent years as a vegan, then a year or so loosely on Schwarzbein, which undid a lot of the veganism damage (fatigue and loss of menstrual cycle), but that put me into being a little too restrictive on carbs, RRARF corrected that.
2) I mostly ate to appetite and didn’t deliberately overeat except maybe some extra cookies, marmalade and honey here and there. I had also spent years following (on and off) Reinhard Engels’ “No S Diet” and that conditioned me into not overeating (the “No Seconds” rule) as well as considering sugary foods to be indulgences best saved for the weekend. I think a mistake people perhaps make is not realizing that RRARF is temporary? Maybe there should be clearer guidelines about what you’re supposed to do after RRARF. I could be wrong, but I saw similar thing happening in the GAPS diet community (I dabbled with that too, only for a few weeks), my understanding is that GAPS is a temporary strict diet to repair gut health, but I spoke to people who had been on it for years for no obvious reason other than it became a habit that stuck.
3) I’m naturally a homebody and cook most of my food from scratch and think that really helps. I went through a phase of eating more convenience food (supermarket ready made meals) when I was working on a house renovation and gained a bit of weight, even though I picked “healthy” options, I think these things contain more PUFAs than I would otherwise eat, rapeseed oil (AKA canola) seems to be in everything here in the UK!