On Thu, 14 Nov 2013 the author wrote to <strathspey@strathspey.org>

The right shoulder pass was a deliberate choice because the two half reels are not the
same - first couple's track during the second half reel is shorter than during the first
half reel. 

The right shoulder pass forces first couple to pass wide which means that they should
finish on the side-lines rather than in from the side-lines - which can easily happen if
they dance the reels at the same speed / in the same way.