I listened to your examples of this left/right dichotomy mentioned in the quote. While changing the beat from time to time has its place and does make music more interesting when used sparingly, is it not true that there is a natural rhythm that occurs that makes us feel comfortable and in sync with this rhythm?In 3/4 time LOUD soft soft sounds natural for the rhythm of the waltz. The waltz would not 'glide' any other way!