Cervantes logic stems from the inverse square rules that affect light emitted from a source. He doesn't make the law, he simply explains the reason behind it. There are variations - type of light, temperature of the lamp, intensity, ambient colours/reflectivity, above all its about using common sense to maximise the efficiency of your own lights and your own setups.
Cervantes knows his shit, and if you dismiss his words purely because you're having little success, I'd have a closer look at your own setup. If you're getting poor results from 1000w, something is seriously wrong with your setup. A light of that power close to your plants will do more damage than benefits offered. Good even coverage at the closest range that is deemable, is vastly more useful to the plant than a super focused spot light covering only part of the plant.
Trimming off fan leaves is just madness. If you want more penetration, tie them down or train them to spread, the fan leaves are the plants main source of energy, its basically a solar panel. If you're cutting them off, expect to cut into the plants potential. There are times to nip/trim the odd branch, but I'm against this widespread belief of trim this, trim that.
Again, people are making growing complicated, especially when they're trying too hard or steamrollering over tried and tested methods.
The best lights in the world will also yield shit results if the genetic potential of the seeds/origin plants aren't great to begin with. Lights aren't magic, they provide the energy for the plant to follow its genetic script. Shit script, shit results. Average lighting will net a larger yield with good genetics, than epic lighting will with shit genetics.
