So regarding an earlier comment, I finally got round to running Lapis Manalis whilst using only GCD heals, assize and no oGCD healing cooldowns. I did habitually hit PI once, but Aquaveil, Benison, Asylum etc were completely off the table.

Lilies and Regen had pretty much everything covered, I had hoped to need to Medica II more but I only ended up casting it twice on the final boss around it's big AoE transition.

Depressingly and perhaps predictably, it made naff all difference.

I got a 94% for my damage which given that I'm not BiS on my healer and don't have a Savage weapon, I'm pretty happy with that.

Dungeon damage is just too low, I suspect I'd have to limit myself to no in combat Lilies, no assize and pray I get a bad tank before no oGCD heals would actually start having an impact.