Ed asked
"The Cecil Sharp tribute concluded with some Morris dancing. Can anyone tell me what the tune was? ... Does it have a particular significance in Sharp's legacy?"

On the 26th December 1899 Cecil Sharp saw Headington Quarry Morris Dances dancing to this tune, Laudnum Bunches, played on the concertina by William Kimber. He wrote down 5 dances that day.

You can see Sharp's manuscript in the Full English archive at http://www.vwml.org/search?qtext=laudnum%20bunches&ts=1392995913024&collectionfilter=HHA;SBG;JHB;LEB;GB;CC;COL;GG;AGG;PG;HAM;MK;

Mitch