Im sure you take booming voice in like almost all situations.
There are some prot warriors I see take in raids, but I think its so they can get the highest parse. Instead of using a gcd to devastate, the dmg is just put into ur auto attack. So while it does little dmg itself, it doenst take anything away from your rotation and is constantly being used every 2.6 sec.
Im sure someone else can explain better though
Its only slighty better for single target it seems.
https://www.warcraftlogs.com/zone/rankings/21#class=Warrior&spec=Protection
You can kinda tell these some of these people are only trying to get good parse by looking at their traits.