Code:
TwistOn 0/1 1= Bard will twist out of combat. TwistOn=0 Bard will NOT twist out of combat (preventing song aggro).
i've also found that having bard use ReturnToCamp=1 instead of shutting off songs useful for avoiding the aggro that you speak of. just be sure to start him behind where you plan to do most of your fighting and he'll run back there. doesn't pass the eyeball test since he returns to the same spot, but you can use ScatterOn=1 to change that. sometimes you will run into issues in tight areas with scatter, however.