Well I've heard off putting the plant in darkness for 2-3 days before switching the light to 12/12, in fact Green House Seed Co's Arjan has advocated it for some of his strains.
I have tried that, it definitely does as described earlier- and tricks them into thinking they are going to die and makes them want to flower to reproduce. It caused several of my plants to flower overnight, however I also saw herms that crop, and had only seen them a few times before in my newb errors and havent since.
I honestly am suprised to hear that you would do this to fully flowered plants. In fact I am inclined to say that you are lucky you haven't hermed your plants doing this. The results of which would be completely disastorus, a bitch to trim, potential seedy nightmare, and a harsher smoke (not to mention diminished jar appeal).
However, many of you seem to have done this before and utilized this technique.
However, I'm with jcdws I'll stick with my purple maxx, overdrive, cha ching, and bud candy for that final shine. I'd rather drop the extra money for nutes that'll pump my trics the whole grow, than risk it at the last day.
I do however know that harvest just before or after the lights come on is the best time. This is shown through roses which when cut in the dawn always smell remarkably better than otherwise cut.
While ganja isnt a rose, its always got the most funk in my room during artificial dawn and its been handed down to me through family members who grow roses
I mean, rose bud? lol.
But I have not since done the 36 hrs of darkness, nor will i do any post harvest darkness. My cured herb gets me pretty high as is, I think my solutions will be found in more light, better ventilation, nutrients, room arrangement. Even free things like, lsting, super cropping, scrog, sog, etc- offer more potentially for increased and better quality harvest than a potentially risky dark period.
But your saying no hermies...
Still skeptical, sorry- if not I guess its just patience then.
And perhaps I'd like to get trimming.