It's all circumstantial, lol.
We have a farm, which means goats, a pond, goose crap, deer poop, many other wonderful treasures that are a sheltie rolling paradise, need I say more?
So, bathing more than every 2-3 months is essential in our circumstance, lol, not compulsive.
I agree.
I'm just saying that for all the city slickers and for those of us who don't live with farm animals. 
I'm also saying it from personal experience. I clean my hair and condition it once every other day. I also have oily hair on top of it. So I had to switch to a dandruff shampoo and condtioner, because my scalp is still dry. Yuck.

I'm so afraid of maltese dogs. Why? Because they are PURE WHITE.
It's soft but fairly short and with a heavy undercoat, so it just sticks straight out, and makes him look about 300 pounds (310 pounds in pictures!)