A lot of people don't realize this, but stress is key to making a plant that is full of THC. This has been well known for other plants for a long time, for example, if you stab a Peyote cactus and let it heal, then stab it again and let it heal etc. It will have more Mescaline in it than a Peyote Cactus that grew happily without being stabbed. Same thing for grass that contains DMT and anything else.
When you kill Male Marijuana Plants, this is a form of Stress. Your Female plants are stressed out, and they make bigger buds that smell stronger. If you let a female Marijuana plant get pollinated it will automatically stop working on its flowers, and concentrate on seed production. This is where "Reggie" Marijuana comes from. Reggie Marijuana is NON STRESSED Marijuana.
Super Cropping is another semi-well known Stress Technique. What you do is let your branches veg to a good length, then snap them gently so the outer "bark" doesn't break. When it heals it will have scar tissue that will allow it to hold more and bigger buds that are stronger. You can also do minor damage with Razor blades.
Topping and FIMing, this is a way to get extra Branches on your plant. You cut the top of, and instead of growing straight up, the plant grows 2 head branches and basically grows as if it were 2 plants. You can do this over and over to get a lot of branches.
Laying Down the Plant, what you do it let the plant grow to 2-4 ft, then grab the top and pin it to the ground. The side of the plant will grow as the new top, and all the branches along the side will act like tops. So you will have 3+ Tops.
Another stress Technique is "Making it Rain" which is letting your plant Dry out to the point where it is wilting or is about to wilt. Then Water it. This allows some Roots to die, then as they grow back over the next week or 2, they will be stronger.
And according to Epigenetics, these plants will release Hormones and if you pollinate them before you harvest so you can get just a few seeds, the seeds (according to Epigenetics) should be effected by these Hormones, and should be better than the parents.