I'm probably making a big mistake by posting here, but I'm hopefully considered to be one of those Berserkers who isn't a "Tool". I group occasionally with Guardians, Monks and Bruisers and the occasional SK/Paladin. Some of which are higher level than me so naturally they take the MT/MA position. They never lose aggro to me if I do not use Bloodlust, I learnt that in the first encounter of the first group I ever offtanked.
It's my golden rule - If you are a Berserker and Offtanking, DO NOT USE BLOODLUST :smileywink: unless asked to by the Main Tank.
It's actually a great tool to pull that last bit of aggro off the MT in an emergency, such as when the MT is running low on HP and the Healer is OOM and there's no scout with an evac.
Flame me if you feel like it, but I reckon that's the way to go. A team player wouldn't argue with you if you asked them not to use Bloodlust except when you needed it.
/salute