Its one of those traits you have to actively take advantage of for it to be terribly useful. Which means really knowing your civics, and finding out the best ones to use in each situation. Ramping up for war? Change to get all the civics that give you experience. Need money? See which combination gives you the most cash. I think the spirituality trait is all about being flexible, and being able to change civics on a dime when your opponent might be stuck with some anarchy. Also, it allows you greater range of civics change. I've noticed that changing all 5 civics will mean more than 1 turn of anarchy, but only changing 1 civic means only one turn. With spirituality, you can change all 5 at once with no turns.
Now, I'm sure there's a strategy for using it effectively that someone else out there can put into words better than me, but obviously the game designers thought it was powerful, because they limited it. You actually can't change civics twice in a row (or even for a few turns i think), so be careful about when you do it.