The original tune is a hornpipe
3c+4c cross on 2nd chord(1,2,3x,4x). This dance has top/bottom symmetry
Note by Drewry: On [65-68] and [69-72] the W use RH twice. This can be avoided by substituting: [65-68] »All set to P | change places passing Rsh, (M face out)«
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.
Note: Cosh explicitly tells 1c to pass Lsh in [9-24]; however the Rsh pass is quite common, and nicknamed »Mairi's Divorce«.