Oh dear I am in the pro FF camp since 2015 or 16.
So many variables that can change people's results me thinks
I currently have over a hundred chickens and turkeys, some are teenagers and babies. I ferment 25 lb a day and they are in a large poultry yard with forage. This is typically what I feed daily.
I harvest most of my cockerels and jakes. They still have fat so they aren't starving. I helped someone with some Orpingtons this fall and they had a lot more fat than my birds internally.
Nov 2020 I got sick, I was feeding 25 lbs FF until then. Cold so no forage but most spring birds had been harvested. I got so I couldn't deal with FF. They ended up eating an extra 10 lbs a day when it was dry. Not sure if they were wasting the pellets, unseen rodents taking them, they ate less because they were full or what. I pickup any uneaten food at night and my birds eat mice.
As soon as I was able I went back to FF. I backslop and ferment 12 hrs usually. Feed bag started lasting 2 days again.
If it doesn't work for you I wouldn't use it either.
I know I eat less calories when I have soup and fill up on water. Lots of people have fat birds from overeating.