How does it not allow you to stack more Power? Removing the mods with Alacrity obviously allows you to put in mods with Power, thus stacking it.
Not to nitpick or anything.
Let's consider the enhancements available to you.
Now explain to me how you can trade Surge for Power?
Having a harder hitting aoe heal and a massive hot is much more useful because of the nature of almost all the ops fights.
Surge clearly benefits Salvation and Rejuvenate more than Alacrity, of course. However, you're still going to be casting Healing Trance and your filler spell of choice, whether it be Deliverance or Benevolence, quite a lot over the course of an encounter, and generally speaking the activation speed boost is going to outweigh the tiny benefit of Surge at that point on the DR curve.
Force Armor gains nothing from either, bemusingly enough.
And lastly, the thread is titled, "Thoughts on Alacrity" so its my opinion on the usefulness of alacrity biased on my countless hours of play time. I'm not saying its correct I just thought I would put it out there for other sages because of the role we play in support healing doesn't really call for faster cast times.
I will add one note: stacking Surge actually increases the value of Crit.