A stout is still judged on clarity in competitions (shine a light through a nice dark stout and it'll have a pretty dark amber color), but if you're not using it in a competition feel free to leave it out. IMO Irish moss is just for preference, if you want it clear then use it.
Two Raven Brewery
[Is finally brewing again!]
Primary1: Envy - Green Tea Wheat (4/11/09)
Secondary: Schwarzbier Kit (1/11/09)
Bottle Conditioning: None ATM
Drinking: None ATM
Up Next: Lemon Honey Pilsner (est. unknown)