Stretching from low light produces very weak stems with nodes far apart and if not addressed, the plant may not have enough light to flower or will produce a plant that is mostly stem. The higher spectrum lights above 3500k help reduce distance between nodes, but will not make much difference to a plant stretching due to insufficient light. The other stretch growers refer to occurs when the plant goes into flower and is natural, but the many myths which try to explain it attribute it to high P flower formulas or genetics.
I defend it against people who brag they got a pound from a plant. 8 tops, 1/4 oz minimum per top without even trying, so there's your 2 oz, and 16 in one gallon bags will fit in a 4x4 tent, so there is your 2 lb. But I'm just a little itty bitty guy and I only grow a few, I like to start a new seed after the current one is mainlined to 8 tops at day 28. I like it because there are no decisions about what to do. I'm a 3rd node,first node, first node auto mainliner. Above the third day 14, at the first node on those two at day 21, and the final top from 4 to 8 at day 28, stand back and watch. I grow mine in one gallon bags filled with nothing but perlite. I drain, then dip, then let sit hempy style for 24 hours. I constantly spray them with distilled water from a hairspray mister bottle. I did all my pruning experiments on a Heavyweight Massive Midget. For almost two years that's all I grew. I pruned it everyway I could think of, all thr known methods. I settled on the 8 top mainline for me. It is totally based on the individual growers personality and what turns him on. But getting back to the Massive midget, when I grew it in 5 gallon smartpot hempies I had a few colas that I couldn't even cram into a jar. And I pack my jars very tight (because I open them up and dump them on a screen every day until they are ready for the humidity pack, which use to be Boveda, but my boveda man crapped out and next time I will use the integra 55 because they come individually sealed. Funny you should ask, I just rolled a massive midget, from long ago, and it's making me talkative.