I always thought it a curious thing that the Argylls' officers sporrans had the normal 6 tassels whilst their levee sporrans had only 5.

Do you recall the feather bonnets situation ? According to various books on the British Army, officers of the Black Watch had 4 fox-tails, the Gordons, Seaforths and Camerons had 5, whilst the Argylls had no less than 6 !