Your continued lack of effort towards your posts does not impress. All we ask is that you use the shift key as called for by English grammar.
The reason i personally ain't gemming for sp is simply because i overheal so much.
In a game where my heal is pretty much always going to heal the target to full and then some, i don't want it to heal harder for even higher green numbers. Instead, i want my heals to land faster, and i want to be able to cast them without running oom longer. Hence haste / int gearing.
The only time in the game i felt the need more spellpower is when i found myself in a situation, where i ran oom too fast by spamming holy lights, but at the same time could not provide a safe level of health restoration to the tank when i switched to flashes. In short, when i was simply not geared for content.