[jtheory]

This is nicely worded, near the end of the review:

But by that final two hours I was, however, not exactly caught up in the music, but surrounded by it, subdued by it, quelled.

There are bound to be things that a piece of music can do to you, with you, if it has 6 hours to become part of your mental landscape... to wait out your normal attempts to "listen" consciously and make sense of it.

I've never been to a similar concert, but it makes me think about long car voyages I've taken with (accidentally) only one CD in the car. Some albums turn to crap after a few hours. Others keep getting better, or more interesting, or a presence you are comfortable with even if it's not moving you anymore.

Interesting stuff to play with, though of course who has the time, normally...