Plant is too small to warrant removing any leaf, photosynthesis by day, cellular respiration 24/7. Even during daylight if a leaf is not performing photosynthesis due to being in a less that optimal position for photosynthesis then it uses that "free oxidative" capacity to perform cellular respiration instead.
95% a new growers focus will be directed towards daylight and the capture of carbon, often giving the illusion that its the end all be all, when its really not. Photosynthesis itself is responsible for about 10% of the energy (ATP), with cellular respiration being responsible for the processing of that other 90% of that energy (ATP)
If you defoliate you remove every single leaf that could potentially perform cellular respiration (daytime), but the only leaves left are 100% photosynthesis. Meaning you are placing 90% of a plants atp pool is processed at night.
Vpd is for daytime transpiration.
There is little to no transpiration at night. Vpd 10x less effective..but good luck finding a guide that will explain that to you. The biggest mistake is holding high daytime rh overnight, not caring what happens at night or jist letting it chill, if RH sits anywhere near 70% there will be next to zero oxidative phosphorylation occurring. Instantly your plant is bottlenecked to 10% of it's daily energetic atp potential. Almost no carbon gets processed and converted.
Defoliating has its time and place, but from my study and experience I find it best to leave everything and let the plant do its thing, at most cut the lowest nodes or "that which you know will be of no use come harvest". How do you know what that is? Experience is the best teacher my friend 🧡.
Mitochondria are the power cells of the plant, removing them is in no way shape or form going to magically open up more budsites. ATP and how much the plant has to spend each cycle is the defining factor of how much "work" gets done.
With a little side lighting you can move from a 2d canopy to a 3d, ensuring that 100% of the plant is properly saturated, zero larf.