Anyone think a transplant in flowering would increase yield (stress aside, because I don't stress my plants when I transplant), or would the results be negligible?
It depends how much room they have now. As long as they have enough room to grow through the end of flowering, transplanting would risk more harm than it's worth. If you want to see what happens with more root room, just use bigger pots next time.
This part here is a somewhat more advanced technique just for people with experience growing their strain(s). Some plants have more continuous growth during flowering while others tend to grow to their full size and then slow growth as the existing bud matures. There are techniques to help prevent plants prone to it from creating new growth just before harvest, flowers that won't have time to mature and will lower the average potency of the plant's buds. Decreasing or eliminating nutrients at the end, flushing the substrate and even manipulating the photoperiod can all help to slow or stop new growth.
Since root confinement slows plant growth (just like with Bonsai), this too can be used to cause more uniform ripening. It's tricky because if you take it just a little too far, the plant will stall and stop ripening altogether. But, by knowing exactly what size container to use when your particular phenos are flowered at a certain size and grown with your precise growing techniques & schedules, you can use the beginning of root binding to your advantage. If the plants begin to become root bound at the very end of flowering but don't stall out, it will decrease new growth and increase the ripening of existing buds. The plant can tell that the source of it's food is starting to have problems and puts everything it has left into procreation, a.k.a. flower formation, before there's nothing left.
I can't stress enough how one mistake here can ruin your plants. Imo the best way to go about applying this technique is by slowly decreasing pot size and/or changing pot shape over the course of many grows. Some of our past internal discussions involved tapering the bottom of the pot to slowly increase the pressure on the roots as they grow at the end of flowering instead of them running into root binding suddenly. I ended up deciding that it wasn't worth the trouble.
Anyway sorry if I rambled on.
