Lots of things work. I can say, eat nothing but lard and jelly bean sandwiches and if you stay in a calories deficit, you'll lose weight. That doesn't mean it isn't stupid or unhealthy.
I've spoken to Tat about this and I think I'm beginning to convince her how bad and unnecessary it is.
Ketosis is a form of starvation. It increases adrenaline and cortisol. It strains the internal organs. It's catabolic. There's no need for it whatsoever, it's just one of those psuedo scientific theories used by the self appointed science geeks that permeated the scene in the 90's. Some people still foolishly follow it. Bad idea.