The four couples can be taken to represent the four experiments round the <<https://home.cern/science/accelerators/large-hadron-collider|LHC>> ring.
The figures (very) vaguely reflect the operation of the LHC starting with injection of “probe” beams (1st couple solo), full circulating “physics” beams round the two rings (interlocking reels), acceleration (right or left hands across and chase) and stable collisions (Schiehallion reel) - though of course the dancers should not actually collide!
The quick turns at the end of bars 12 and 20 are quite contrary to the way the proton beams behave but allow the dancers to change direction from time to time.
The Schiehallion reel is only three quarters to suggest that quite often the LHC fills are interrupted earlier than expected due to one of the many safety systems cutting in.