Not really, but wouldn't it be easier to make a new quality for the rude and irritable troll than to try and force it into Uncouth which isn't designed for it?
Uncouth people have no idea how to act in social situations. If you play an uncouth character and that dwarf is trying to scare you, guess what, you get scared. You piss your pant and cry like a baby, because you don't know how not to. You have no ability to cope with it. Its a 20BP flaw for a reason.
If you want to make your troll rude, obnoxious, and just generally a pain in the ass to be around, give him these:
Poor Self Control: What a Bastard (5 BP)
Characters with this flaw are generally considered to be self important and have little care for others thoughts and opinions. While they think this makes them stronger, it also hampers their ability to successfully manipulate others. Character's with this flaw cannot purchase the Influence skill group and must pay double for every rank in Negotiation or Con. Characters without ranks in these skills are considered unaware in them. The GM may require these character's to make rolls for things that normally would not require a roll.
Sample Quote: Tell us where the stuff's at, so I can shoot ya.
Poor Self Control: Rude and Obnoxious (5 BP)
Characters with this flaw are unable to blend in with society. They either constantly feel the need to clumsily be the center of attention, or they just don't care enough to conform to polite standards. Character's with this flaw cannot purchase the Influence skill group, and must pay double for every rank in Etiquette. Characters with no rank in this skill are treated as unaware in it. The GM may require the character to make roll for things that normally would not require a roll.
Sample Quote: Little Kaylee here just wishes you was a gynecologist.