#3: It's scratchy.

Denton's #1 observation about growing a moustache:

Yes. I've got some dirt on my face. That's very humorous, and I never thought about it that way before. Even if the comparison had occurred to me, it certainly had never been put forth by 40% of the entire greenhouse before you.

That's not what prompted me to shave it off, though. No, the blame for that lies on observation #2: Accessorizing.

Moustache + glasses: intelligent.
Moustache + pipe: dignified.
Moustache + T-shirt: hard-workin' man.
Moustache + kilt: dancing-on-the-ceiling crazy person.
Moustache + Hawaiian shirt: Magnum, P.I.

Believe me, that last one carried some weight. However...

Moustache + bunnyhug: creepy old man.

I try and I try, but I just can't find any way around it. Ah, well. At least now, I know for sure.