Hi! The meaning of this tutorial is to help other 3d-coat users to get their Ptex texture into regular or normal uv-set. There is a couple points why this is good thing: 1)You don't have to worry UV before starting to paint. 2) You can paint with Ptex as detail textures you want. Because in the end you can choose resolution for normal uv-set almost all detail will transfer if you want. 3) Sometimes PTex will create 2 or more UV-sets. This is the way how you can bring them together again.