I use riddle's boiling method. If your not familiar with it, you do a normal watering but with boiling water 3 days before you chop. This is for quality, not quantity. As to the why, here's a copied explanation from chuck estevez
the whole point of his process is FERMENTATION. the plant is full of glucose,sugars,starches. How do you make those ferment? Cut off the oxygen they receive. So, you come to the end and you are ready to chop, You pour the water on the roots, therefore, killing them, WHALLA, no oxygen getting to roots, said sugars etc, start to ferment. So the curing starts happening after about 3 days of no o2. And you will see the plant wilt after a couple days and change color, someone mentioned earlier about it being a pain to cut them off after doing this, easy solution, cut fan leaves off over that 3 day waiting period.
Basically just starts the curing process earlier to improve quality.