Stick Time: The Educational Value of Jazz

Today we consider a little Vocal Jazz (and no, to answer the question I ask in today's Choral Caffeine, 'Jazz' is NOT a dirty word).  Listen to this recording and consider just a couple things. How carefully must the singers LISTEN to tune those challenging 7th, 9th and 11th chords?  How exactly must singers match vowels to acheive such a great blend?  How well must the soloist understand HARMONIC THEORY in order to improvise (quite successfully) over a constantly changing chordal progression?  As you're listening, read "To Jazz or Not To Jazz" by James McCullough.