Hi Westy,
I would never ration youngsters, all the time they are growing. Feed until they are satisfied. I let mine out once a day in the afternoon, to avoid flyaways
( we've had a post on this ) and by this time, they are again looking for their daily feed.
When you're training them of course, then that is a different thing, then you can reduce their feed to control them.
I think you're right in only feeding once a day, after their exercise.