I have found that I forget to validate when using displacement and then lose it so I am glad I have been practicing. You can't get it back with undo either. So if you have beeen working for awhile and then change tools or several other things you can lose it. However, I am getting a bit better with both. UV stuff is never easy tho no matter what you use. There is an art to it.

No need to think outside the box....
    Just make it invisible.