So, is Derek Waters an alcoholic?

I've seen functioning alcoholics achieve a lot. Case in point, Dan Harmon.

That being said, I think it's pretty obvious to anyone that watches the show that Derek has to do a tremendous amount of talent wrangling, occasionally with talent that's impossible to wrangle, so while it does show him drinking with the guest, there's not a chance in heck he's drinking as much as the guest. I have no doubt that he's drinking exactly what you see him drink on camera- and not a drop more- because the tipsier he gets, the harder it will be to keep the drunk actors in line.

While it may look, on the outside, that this show just involves giving an actor a story to tell and a bunch of drinks, there's way more work involved. You try getting someone really drunk and then have them do what you want them to do. You might as well be trying to herd cats. Derek works hard- as does the rest of the crew.

no one is actually drinking during this - the ones in costume are not the only ones acting.