It does work, some people swear by it. We don't do it because we like the heavy milkers to be able to lie down in peace and eat their food, without hungry kids or goatlings hoovering it up. However we do normally pen kids together, and goatlings too.
If your pens are easily rearranged, it might be worth a try. I'd love enough room to have a big "day pen" so that they could spent the day together as a herd even when the weather is rubbish.
Beth