I played round with it last night and managaed to get through Tol'Vir normal fairly painlessly just using

/castsequence [@focustargettarget] riptide, healing wave, healing wave, chain heal

With totally undergeared healer I had almost no mana issues during fights (having to drink maybe every 4 pulls) and bosses like the third one where I don't have to worry about damage to the team if I pay attention were easy but fights like the first one where I have to heal someone that may not have agro is a pain. I think that's because the healing macro is on both my normal and aoe spam keys and so it's hard to find a gcd to do other heals as I'm spamming my 2-step.

I'm fairly certain the solution to this is just create another 2-step that will only fire on my tank and dps so I can then use grid healing to do specific heals and cleanses as needed.