This guy who told you that, seems to know what he is talking about. I like him!I know of a guy who would say that you have gone to deep into the fasting and low calories with all of the resistance training. That guy would make mention of the fact your recent weight gain is VERY likely water retention from excessively high cortisol levels that will slow fat loss and rob you of hard earned muscle. That guy might suggest IntraWorkout supplementation like carbs and whey isolate to stave off this effect, and prolong the diet. He may even push the subject since you are now willing to introduce supplements to treat symptoms of this situation like a stimmed diet powder. Now that the "keeping as basic as possible" principle is not being used. Perhaps you could consider other supplements that could resolve the issue and clear up the symptoms instead of just tossing something for energy on top of it.
In other words... don't toss gasoline on the fire to get the flames up while your house is burning down... add things to resolve the issue instead if you are going to add something.
I know you do have a plan and are testing a theory or idea out. I know what the results will end up being with the current strategy and am just trying to provide some options to help improve the process, rather than only being a cheerleader for you.
Have "Karbolyn" at hand for intra workout carb supplementation, I also have a bottle of "Invictus" laying around, for cortisol control.
Like most guys here on AM, I have a fridge full of goodies, waiting to be used.