Pretty Good advice, except for the bit about unbinding DI.
As a top heal sorc on my server, I find DI more difficult to use efficiently after 1.2, but it is absolutely essential. Dark Heal is very inefficient in terms of HPCT and Force cost. Only use Dark Heal for "oh s**t" situations where someone is about to be blown up.
If you are timing your heals right, you should be keeping Resurg/ Innervate on CD and casting DI whenever possible. If you get interrupted, try to root/mezz your attacker bubble, by that time innervate will be up.