There is a description in geometry of a three dimensional sprial shape called the helicoid. Its distinguished as the "only non-rotary surface which can glide along itself." I know nothing of geometry, but I'll take a bit of imaginative license here to declare Tony Levin's stick work and the elliptical interplay of guitars on this performance as "helicoid" in shape. A great way to propel the musical action forward bookended by the concert opener Neurotica and Pictures of a City at the Denver show (Bellco Theater, June 24, 2017). I've only heard this composition previously as the studio recorded rendering. So working Mel Collins' flute and sax parts into the composition was a special treat. Another example of the expertly sequenced playlist and a board recording that's virtually as clean as a whistle. (No whistles in this recording,btw,except those of the expressive variety from an appreciative audience). Thanks for including one from the Denver date.