Greetings all. Looking for a perspective on this quotation posted on a forum in another place.

"The Art of War is much changed and improved here. I suppose by the End of Summer it will have undergone a total revolution... The Highlanders have put on Breeches and Lord How's Filabegs."

Dr. Richard Huck to the Earl of Loudon, May 29, 1758.

This is something I had not heard of.
(Breeches apparently noted in Regimental Orders order for the 42nd for the next 3 years.)

Key question, I suppose: what is the distinguishing element that merits the description 'Lord How's Filabegs?