First sorry but it’s hard to compare this plant with people in terms of growth. There is no real common point to begin a discussion and have it make any since.
First plants store energy they do not turn it to fat. Plants don’t need to workout and thin is not in with plants. The larger the plant get the more energy they can store but in turn the more energy they need just to maintain that same level of growth.

Large fan leafs are used to help the plant control the internal temperature of the liquid in the plant thus the temperature of the whole plant. Plants work in more of a reverse manor, when they transpire they are working to hard and spending energy doing other things rather then just growing more foliage and flowers... Your compartment of this to people is only confusing the facts. You said most of the theory properly but you keep trying to compare it to people fat from what I can tell.

By having high humidity in the vegetation cycle the plant is allowed to spend its energy into producing foliage above the root line and it does not need to build mass roots (in hydro) the drippers deliver all the required nutrients to the plant when it needs it.

I assume you have checked out my Cycle of Life growing technique already.