Hrm… interesting. But she missed something. If its true that water replaces the fat, I have never heard of this before, but what the heck, learn me something, if the cell remains the same size, the same volume, and its the fat is replaced with water, there will be a net weight gain. Water is denser than fat. The same volume of water weighs [give me a minute, I need to google a bit, I’ll be right back, I promise. Wow you waited, sorry it took so long. Google was having an attitude]
So fat weighs in at 1.98 pounds per liter (google would only find it in this strange form of pounds and liters. Very odd.
Water weighs in at 1 KG per liter. (Inconsistent much google?)
So per liter, water is 2.2 pounds and fat is 1.98. Some quick napkin math puts fat at 90% the weight of water.
Sooooo… if the fat replaced by water was near instant, then as you burned off fat you would slowly be gaining weight. Wait, nope. You already have that water in your system. So there is a small weight loss initially. Until the nextime you hydrate. Then you will gain 1.1 pounds of water in your fat cells for every pound of fat loss. With no measurements changing, seeing as the cells are retaining their original volume.
Until later when you run into a tree and then “whoosh”. You end up like a crew on a space ship that goes to warp speed without its inertia dampers working.