A small note to use CH for main tank healing.
On quite a few bosses the tank(s) tends to not want melee on them because of cleave and etc. Thus chain heal will have less effect for the MT healing. Still its worth throwing on quite a lot of fights, as the range is quite high, and the chance that it will jump and make it even more efficient is quite high.
Also the CD on Riptide is 6 seconds, and to refresh the 30% speed buff for Healing wave, chain heal is a good option, if you cant wait for the Riptide to get off CD.