Generally speaking, the main difference between a casual kilt and a "real" kilt is that the casual, although pleated in the manner of a real kilt, has no hair canvas to help shape the hips, nor a reinforcement of the pleats at the waist and a full lining. Also On the real version the excess material in the pleats at the waist is cut out. On the other hand, the excess material of the casual kilts is left in. If you were to have a kilt made with your 6 1/2 yards of tartan, and have it constructed like a real kilt, it would be a real kilt, and not a casual kilt, the way I look at things. Also, remember that the idea that a real kilt is made of eight yards is a fairly recent fashion in the kilt world. In earlier times small kilts were made with as little as three to 3 1/2 yards, and for quite some time were regularly made with four yards, give or take, maybe five yards for a larger sized kilt. These shorter yardage kilts were in there day considered real kilts.

(Fundamentalists, please not I use the word real above only to very much simplify expression of my thoughts, and not out of contempt for your dogma.)