as far as snapping the stem, its called supercropping. look it up here. i use it sometimes to slow down the growth of a single branch. while it heals itself the others can catch up and even out the canopy. one thing of note. the spot you crunched the stem will get big, and everything above that spot tends to grow bigger. very handy technique to know. remember though over-loving these plants can do more harm than good...
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