so from what i understand, putting a plant through stress is good, makes them more resilient, thicker stemmed and heavier yeilding. but if a plant goes through too much stress, will it just stop growing? i say this because a kush of mine had a hard time as a cutting, it has improved and almost floureshed....except in its own pint sized way. VERY close nodes, barley 6 inches tall. i always through stunted growth was for a period of time...then it came back stronger than ever. guess not?
From what I have seen, stressing seedlings or new clones will likely be more detrimental than productive. I have read very interesting stories about stressing established plants to increase resin production, but stressing a plant necessarily means that the plant has to direct energy and resources to dealing with the stressor -- which could detract from its ability to flower to its full potential. I personally try to avoid any stress until I'm well into flowering.
To much stress can turn your plant into a hermie, so be careful. From what i've read, stress can also be a good thing (just not to much) by, as you said, making thicker stems and a few other things. If you have a male plant (and your doing a small grow, or have more than one room) you can stress the hell out of it (fuck with the light, break stems, underwater, and over water) so that it'll hermie, and you can get something smokeable out of it.