What is your preference for a player to get a commendation?

[Yeol]

On a similar note, when I was first leveling ninja, my first melee DPS class, I was scolded for using LB on 2nd boss when it had about 50% HP remaining. Since that time, I've been hesitant to use LB until about 15% or slightly less, depending on the boss.

Oh yes. You should never wait and use it as soon as it pops (unless like you said, waiting for an AoE to be safe). If people get angry, just wait till the end of the fight and tell them it made no difference. The damage it does will remain the same whether used at the beginning or the end. Also, sometimes if you are lucky enough it might pop again near the end of the fight! It even might help you speed through some phases.