3C Chain Progression was earlier known as Chaperoned Chain Progression
A quote: »the key that has always made this dance so wonderful is the flirting that dancing couple can do on bars 9-10 and 13-14 ; <...> if you actually set to your partner, advancing and at the last moment just slipping in BtoB to face and turn the appropriate corner, it's tremendous fun. The moment is all too rare, as apparently few teachers teach it this way, but it's a moment I savour.
On bar 24 1M ends between 3s facing up & 1L between 2s facing down
1s now repeat the dance as opposite gender
In 17-32, the corners traditionally set one bar to the person you just passed, then one bar to the next person to pass. In a variant for [19-24] 1c turns BH in PdB.