You certainly did your homework. This is one analytical question I can respond to without provoking the DYOH Squad. I think I found the source of your problem: The ritornello is more obvious in the original Marcello version. Bach is never one to bore the listener with note-for-note repetition, so he varies the ritornello every time. In fact, Bach was not even confident that the listener will sit through all those ritornellos even with the variations. He cuts out entire ritornello sections in ms. 44 and 48. Listen to the original Marcello version here: http://www.youtube.com/watch?v=UY449k-or… You may notice that this piece has more cadences than most of Bach’s original compositions. This is partly each solo passage and each orchestral passage has to end on a cadence. This is also partly because composers of Bach’s stature are more skilled in keeping the listener attentive longer. Here is a good arti