It's a hobby. Whether you think it's healthy or not doesn't give you any reason to say he's got issues.
You get a grace period if you get disconnected. It's pretty short though.
Eh, I'd take a look at his average playtime and the way it's affecting his life if you really want to see if this is "healthy". I don't think getting uber-excited about a new game you've been anticipating for a long time and binge-playing it is 'unhealthy', it's not like he's doing it 24 hours for the next two weeks. A lot of us have had considerable gaming marathons like this.
Well I have never had a marathon of gaming in my life. But the thought of playing 20 hours straight doesnt seem healthy Hey but that's just me and my almost 30 old ass.