I am prone to think this notion of free feeding may not work the same in confinement as it does when birds range. I think when birds range all day, even if it's in a limited space lile some of mine, it doesn't make such a difference.We do free-feeding. Birds have access to multiple feed stations all day long.
I have been free feeding dry types of food for four years now and what I'm seeing is that chickens certainly don't eat continuously all day, if only because once they move away from where the feeders are located, they will only come back to feed when they make a conscious decision to move to where the feed stations are.
This happens more than the three times a day I give them fermented food and wet mash, but not more I think than five times a day.
The only times I've seen chickens act like they are spending much more time at the feeders, are when they are making the transition from set time feeding to free feeding : when I brought adult birds in that had been used to being restrained feeding.
(Leaving dry food accessible at all time has not had any impact that I can tell on the fact that I have two hens turning broody far too often, two that turn broody once or twice a year, and 11 that have not shown signs of turning broody, eight of which still could as they are less than a year.).