As a SCH, no it's not necessary, but it does help. For dungeons, I personally throw on SS onto party members as a starting measure to find out who are the troublesome DPS who are going to drive me insane (because the troublesome ones will ALWAYS lose it fast), and Galvanize before pulls simply because I want to make sure I have enough time to throw out a Shadow Flare to slow the enemies down and do some damage while I'm healing. For Trials, that Adlo is useful for at least the first strike of the fight, giving me enough time to throw on the DoT combo to help with the starting damage before settling down into my healing cycle.