If you go for the second haste breakpoint, it gives ticks on HTT / HST. Why would you recall HST using the glyph if you've statted for that breakpoint? Also GCDs, which could be spent actually healing. The glyph may give you some mana back in a fight, but imo it isn't worth a GCD every time you HST / fire / earth ele.
You have the GCD's for recalls. And the 100k+ mana you save can be used for more healing. And less spirit. How much spirit is 200k mana saved in recalls? Those stats can then be used for crit/mastery, which further increase your healing. Far moreso than the GCD used to do the recalls imo. And with all the people in here saying use TC, you can't tell me with a straight face and say there isn't time for spending a GCD here and there for big mana return. This isn't wrath anymore.
As for losing the last tick of HST. if it happens, meh, so what. I lost 10% of my HST at the cost of 200k mana saved. zomg, totally not worth it. And you don't recall HTT. It's cheap. Just recall HST and elementals.
i only use the riptide glyph when tank healing at stoneguard hc, in this fight i cant afford to have non-tidal waves pushed casts, + there is nearly no overheal from it. i just spam a fixed rotation with rt hs*2 and an occasional healingrain on the melee camp, while starting to chaining cds as soon as the fight starts. If green is on petrification, its a big relief on healers. 3 healers at roundabout 80 k hps overall with nearly zero overheal is pretty hard for the first heroic boss in an expansion.
At the running phase in 2nd boss in heart of fear (which we had to 2heal due to enrage timer) i am fine with healing tide totem into healing stream totem for the first run, and ascendance + spritwalkers grace into healing stream for the 2nd run.
and i agree with going mastery over crit for heart of fear instance, the first 4 bosses there i have met are really high in burst-aehealing reqirements.