OC Richard... Nice pictures, but I would say that Clan Chiefs in Scotland, on parade, pretty well wear what the wish and are never too traditional. They have an "expected" appearance. If they all took to wearing Bowler hats would you walk up to one and say, "I say, that is not the way it is done." They are a separate group.

Pipers are also a distinct group. You look very dashing in the picture. You are not in Costume as a piper, but in expected dress.