A kilt ceases to be a kilt when one of two three things happens...

1). The wearer considers it a skirt,
2). It's worn with no tradition or thought for heritage,
3). The wearer accessorizes it with inappropriate things.
In my opinion, the kilt is so much more than a garment. When it's treated as something that it's not... it comes across in the appearance. Frilly shirt, pleated garment and a pair of Mary-Janes make it a skirt. On the other hand, a simple UtiliKilt with the proper accessories becomes a solid kilt.

It's always been my contention that a "kilt" is more a state of mind. It's just a WHOLE lot easier to get that feeling when the thing is wool, heavily pleated, made with skill, and accessorized appropriately.