In my last play through I had Konstenten with the Frenzy upgrade that Frightens and the amount of disengagement attacks went up by a lot.  The game does not always correctly remove engagement when an enemy is feared.  This could give an Unbroken some good opportunities for forcing disengagement attacks.  Remember that a lot of the time frighten does remove engagement , but sometimes it does not!

It seems to be kind of borked. Somebody reported that it works better with Turn Based mode then with RTwP.

What I've observed, in particular with the Fear Totem, is that once Terrified, they can be quickly renegaged, and will often break engagement after that. It may be the case, also, that the Terrify from the Totem doesn't give them a free "disengage" because it's not engaging them. If you wanted to play around with the mechanics, I recommend trying it out.