Though this would help extensively, I do not believe the Highlanders would be there en masse. THey share a comeraderie with the Royal Black Watch and constantly exchange warriors. At least 2-3 of their regiments would be employed on the SLDF side of things, might get hairy. Remember, during this period, the Highlanders are Hegemony based, not Capellan Confederation based, as Liao didn't get Northwind until after the fall of the Star League.