Also, don't forget the other major manual used by both sides written by Maj. William Gilham. A very popular system and more true to Scott's manual than Hardee was. Gilham allowed for the use of 1 or 2 colors. There are also a number of confederate units that use the 2 flag system at one time or anther, but not always (usually early war). Much better than the Prussian system, and also much better than Von Steuben's system from the revolution as well.