Personally, I believe defoliation at any time to be a bad idea, but defoliating a plant the size of yours would have to be the absolute worst time to do so.
Defoliation only reduces your plants capacity to produce energy, which obviously slows growth.
Defoliating plants that only have 2-6 big "fan" leaves would reduce the energy making ability by a large percentage.
Limp leaves are not a result of low light , but a result of thirst.
Light we humans can not see will actually penetrate upper leaves and strike lower leaves and stimulate photosynthesis, thereby providing at least some energy for growth and a lot more energy than no leaf. The branches that are shaded will grow out from underneath the fan leaves and are relying on those fan leaves to make the energy so they can grow. The small leaves growing on the branches can in no way produce as much energy as even just one fan leaf.
The theory that plants will "use stored carbs from the roots for growth" is fanciful at best. For a start, even if it were true, how did the plant accumulate carbs to store in the roots? The only way a plant makes carbs is through photosynthesis, which relies on leaves, so a reduction in leaves would mean less carbs being made and much less ability to "store" any "excess" carbs. Would it not be better to have the leaves AND excess carbs and not have to use "stored carbs" as an emergency reserve in the first place!?! Then to "regrow leaves after defoliation has occurred" is also absurd - why defoliate just to grow new leaves?!! For your cannabis plant to grow her biggest and fastest, she needs EVERY leaf she has to produce the energy she needs for growth. Try only removing yellow leaves - for by the time they are yellow, they have served their purpose. I have been growing for 35+ years and am yet to see a plant that gets rid of its own healthy green leaves for no apparent reason or benefit. Cannabis has evolved to grow her biggest and fastest the way it is doing so now. This does not involve defoliation of healthy green leaves.
Remember - maximum amount of healthy green leaves = maximum energy production = maximum growth and maximum health.
Yes, it is that simple, and basic plant biology 101.
Hope this helps,........
Organoman.