Here is a #necktie knot I have seen named elsewhere as a "Persian", but in The 85 Ways to Tie a Tie is just listed as a variant of a Windsor.

The difference is that it reverses some moves in a way that at the end has a negligible (I'm almost prepared to day no effect) effect on the appearance. Probably lots of people use this #knot and has no idea it's not a "standard" Windsor.