Quote Originally Posted by Calgacus View Post

As for the portrait of William Cunning, Piper to Lord Grant, 1715, yes it's a portrait and could be factually incorrect, but it shows the material to be apparently doubled in two areas as shown below-

Grant piper big highlight.jpg

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Maybe I am misunderstanding your point, but isn't that "doubling" simply the upper half of the plaid, drooping down over the belt before being pulled up to the shoulder??