Depends on the fight and generally how the community as a whole was doing. Just to clarify as an example, I would actively tell dps not to LB during fights like Scathach and Hollow Diabolos because of how easily things could go wrong at the end.

Whereas on a fight like lahkshmi ex you may as well just dps LB her because, lets be honest here, if you actually need the healer LB3 to beat lahkshmi ex? I don't even know what to say to that.