I have absolutely used tank LB to save parties from their screw-ups, or to simply cheese mechanic. And of course, when needed due to fight script.
Of course I’m a DPS-oriented game like this, it’s still the vast minority of times. But it can be used well.

Sadly it seems SE doesn’t like creative liberties. A lot of new mechanics are insta-wipe ignoring limit breaks and such. Sad times.