User blog comment:FairyRaven/Fairy Tail Chapter 335: The Time of Life, Review and Commentary/@comment-5840892-20130614190903/@comment-4829046-20130615045817

That's just positive thinking. Also we learnt from DBZ that some suicide abilities still leave the user alive, just barely.

It takes a lot more effort to rewind time than it is to fast forward it. You literally have to undo fate by doing so and of course that is taboo.

Still the fact that Erza can bend the laws of magic without getting drawbacks is proof that your theory is still there.