Pretty much every time you are struggling healing one of several things has happened:
- You didn’t pre-hot for major damage phase
- The tank isn’t using mitigation skills (I’ve seen DH’s with less than 10% uptime on demon spikes and guardian druid frequently not having iron fur up mid pull)
- The group isn’t doing mechanics properly
- The group isn’t interrupting key abilities
Pretty much the only thing on this list that’s on you is the first one and trust me other healers have a lot more trouble than us with sustained group healing. De other side is a great instance to know how well your group handles mechanics because most of the fights there are actually really light on healing unless people start screwing up and if that happens it very quickly goes bad.