The regulations for levees required military officers to follow the full-dress regulations of their respective regiments. Sometime around the turn of the 20th century these regulations began to include the full-dress brogue with the ankle strap. As with everything else regarding uniform changes, during the period of actually changing over, "old pattern" clothing was allowed to be worn until no longer serviceable. Likewise, some regiments had specific dress regulations for levee dress which did include "court shoes with buckles".

Gentlemen, when attending a levee in civilian Highland attire wore full-dress brogues with buckles on the instep and ankle (see Dress Worn at Court, 1910 et seq). These same shoes were, and are, worn with ordinary Highland formal attire as well (although the sword belts, swords, full plaids, etc., required for levee dress are no longer worn with civilian formal attire).

So why the ankle strap on full-dress brogues? Quite simply to keep the shoe on the foot when engaged in the exuberance of Highland dancing!