I'll try to get back on topic...
I was a bit surprised that I didn't post in this thread first time around.
Different circumstances bring out different thoughts/actions/reactions. In performance I'm often monitoring my internal state to stay relaxed. Tension is a problem; it can really slow down your responses. My focus can shift from listening "within" to paying more attention to what my bandmates are up to.
One issue that I have yet to overcome is when playing large outdoor festivals, or perhaps this happens in theaters as well. It seems that I often feel drained after about the halfway mark in the show. The difference seems to be just the fact of us being on a stage, under lights, with an audience sitting and listening. I find it very easy to relax and let the flow happen when the music is in a more social environment. Maybe I just need to go through those situations more often, and look for a tactic of some sort. Anyone else know what I'm talking about?