Ivor kindly sent us his copy of the aforementioned article(A NOTE ON THE SHETLAND SWORD DANCE by James E. Spears,University of Tennessee at Martin: Southern Folklore Quarterly Vol 32 No 4 Dec 1969).He himself doesn't wish to research this area.
To me, the links appear pretty tenuous, and more relating to the
calling-on:
"The imagery and language, substance and/or symbolic action, and the survival of the play in Yorkshire could suggest that the Shetland Sword Dance is linked with the institution of Freemasonry.
At least three images used ... in the dance are reminiscent of the rites of Freemasonry and are germane to its vocabulary: tried, right hand and raised."
http://www.papastour.shetland.co.uk/dance.html