OK, I'll bite and slap another hand.
Oh yeah, for those that constantly go back to the nature argument and how nature put the fan leaves there for a reason and bla bla bla, understand that by bringing that plant indoors and trying to duplicate outdoor conditions you're already disturbing the natural process...
You're not disturbing a thing, that is if you're successfully replicating natural plant processes like you should be doing. Do you understand what a photon is and how and why the leaf collects them? Plant doesn't care if the photons come from the sun or a lamp. Your argument is about as ill founded as the old "you need to have MH for vegetation and HPS for flowering." Speaking of gimmicks..... I've grown better pot using a regular HPS exclusively from start to finish than most falling for (and using) the lamp switch-a-roo drill, conversion lamps or "enhanced" lamps that vendors like but plants could care less about.
..... and certain things may need to be tweaked, such as opening up the canopy by plucking some fan leaves or by trimming the bottom 1/3rd of the plant because it's not going to fully develop because of lack of light energy from your unnatural sun.
Certain things don't need to be tweaked, naturally grown is best. You can play games with the plant by opening up the canopy or training, but you best understand plant processes (photosynthesis, hormonal responses) before you do. I never plucked leaves and my yields are always high. Then again, I know how to tweak all factors that go into the final equation - temps, watering, nutrition, light, diurnal temp swing, air movement, etc.
The bottom doesn't fully develop because it's the last to produce and mature and by that time this annual's life is pretty much done with. This plant response is a result of a natural process called apical dominance, a hormonal response found in ALL plant material whether it be cannabis, peach tree, pecan, or tomato plant. The top of any perennial or annual is gonna get most of "the goodies" all the time, every time. That's just what nature does.
I can get another ounce or so out of the bottom of an indoor grown plant by harvesting the bulked up colas and then putting the plant back under the lights for a while. You gotta have healthy leaves left on the plant to pull it off, duh. In the typical garden that won't work thanks to another ill founded noobie paradigm that "it's normal for a plant to lose all of its fan leaves by harvest"......as some ignoramous uses foods that induce leaf drop or just don't know what they are doing other than following crap advice in cannabis forums.
Hope this addresses your question, for about the hundredth time.
UB