So...
I have a flock that free ranges (see my signature, below). I've hit upon a management method that works for me, and seems to be unique among BYC posters. I can't find a single study that provides the illusion of "science" behind what I've stumbled into.
In short, this is an anecdote, and as advice, is worth not more, and perhaps less, than you paid for it.
I feed my birds once a day. At night. In the run. This encourages everyone to come to the run, and thus the coop, at night for a "free feeding". Which allows me to observe behaviors, look for signs of injury, get a head count, and make certain everyone goes to bed at night with a full crop. Seasonally, I find feed savings between 20-35% against expected consumption.
It also means that the birds know they aren't getting fed again till next sunset - so when I open the gates between 6 and 7am, they are awful eager to go bug hunting and grass/grain nibbling in my biodiverse polyculture (acres of weeds).