If your birds are let out to a large area where they can free range, yes they may be OK with feeding once (or preferably twice) a day. But if you keep them in an enclosed run, or don't have enough good free range grazing, I think they do need feed available all the day time. Chickens are not like us, they don't take regular meals at set times with gaps in between, they feed mostly by frequent nibbles and if they don't have food for hours, will then stuff themselves to fill their empty crops, which isn't good for their digestion. Also, you wouldn't be able to tell whether the lower-ranking birds had had enough, if all their feed was gone.
I feel more comfortable leaving food out for them, at least during the day, as mine live in a big run with no access to wild birds or vermin. They don't seem to get fat, but If they're left hungry for long periods waiting for a meal, i'm sure egg production would drop, as well as causing discomfort to the birds. Removing the feeder at night is a good idea, - providing you can get up early enough to replace it at dawn, when they wake up very hungry.