I'd like to point out again that I never claimed Spell Speed truly superior to Crit. As far as potency and damage goes Crit will outweigh any other stat, but I offered that Spell speed provides unique advantages crit cannot, and as such should not be discredited. Our secondary choices do not matter too much in the end, after all I've seen content solo'd with SpS/Pie builds on Scholar. Does that mean it's the best build a Scholar can have? No, it was just what that individual chose. Healing is as others have said a very binary existence. SpS can easily be the difference between pass or fail, whereas a crit is the difference between pass or pass harder.

If you want to play the numbers game, by all means feel free to chose Crit. Chances are you'll do just fine, because we healer's don't care about measuring out the absolute 1% extra HPS possible. If I played White Mage I would choose Spell Speed, but if you're content with Determination or Critical then by all means have fun with it. Unlike DPS, Healers are free to choose the stat weight that suits their style more. We aren't burdened into min-maxing every single point of HPS.