Ally Bain recorded Margaret's as a lovely air.  I think that helped its popularity.
I was at a session in Stirling, Scotland and we played Margaret's.  I played it as I'd learned it, as a dance.  When we ended, one of the other players said, "Now let's play it the way it should be played."  We all played it again, as an air.
Sylvia Miskoe, Concord NH

On Thu, Dec 29, 2016 at 3:04 AM, Colin Hume colin@colinhume.com [trad-dance-callers] <trad-dance-callers@yahoogroups.com> wrote:
 

On Wed, 28 Dec 2016 23:28:03 -0500, Sylvia Miskoe sylviasmiskoe@gmail.com [trad-dance-callers] wrote:
> Pat Shaw wrote a companion waltz, Farewell to Devon, in honor of Margaret when she moved from Devon.
> It has faded into obscurity.

Maybe that's because it doesn't have its own dance associated with it.
Pat intended both tunes to be played for Margaret's Waltz, and many bands in England do so.

Colin Hume