Which Part of the Moment?

Recently I've been pondering the idea of "living in the moment."  The phrase sounds virtuous in its simplicity, but I'm not finding it all that simple.

Parts of it I get.  When I look at each of my children and am occasionally overwhelmed with how fast it's all going by, I try very hard to really look at them.  I want to be present and appreciate who they are at that specific time.  When I'm at a concert I try to clear my mind as best I can of the flutter of mental distractions that vie for my attention so I can truly hear the music as it's happening.  When I practice I know I need to focus in order to be productive.  When I snuggle up against my husband at night, I know not to take such basic comforts for granted.

I've even learned to accept living in the moment when it involves pain.  Occasionally I suffer debilitating headaches, and I've found the best thing to do is not to resist.  When I took birthing classes before having Aden I remember the instructor refusing to use the word pain to talk about labor, preferring to tell her pregnant and nervous pupils that it was merely "an interesting sensation."  That, frankly, is disingenuous at best, but there is something to it.  If you don't have a choice about being in pain, fighting it adds to its intensity.  Better to relax and find it "an interesting sensation" if possible.

So I see the value of "living in the moment."  The problem I'm having is that the phrase seems to imply that there is only one thing in that moment.  What if the moment is multi-faceted?  What if living in the moment is about reflecting on the past or planning for the future?  What about all the choices you might have to make about what living in the moment actually means?