No idea. I reckon the idea is that you project your appearance to the target so that the enemy thinks that's the real you and thus everything you, the supposed clone, do is attributed to that person instead. Except that changing somebody else's appearance was considered annoying and thus not implemented.

It was a little bit disappointing, just as duality, where I expected a clone to briefly appear and do the same attack/animation as I. Instead, my character waves her daggers around a bit and the next weapon skill simply pops two numbers instead of one. Yaaaaay!