i'll have to do more research on that whole dark cycle thing. but so far im trying to just weaken my nutrients over time. with my first grow i didn't use any nutrients because i couldn't since it was raining almost daily. plant grew nicely but i couldn't smoke it or anything to tell since we gave the buds away to my dads friend who was watching his male plantsI taper the feed down during the last 3 weeks or so. Fed lightly to the last watering or two.
If fed properly no need to leach pots.
And I dont leave them in the dark. I do harvest at lights on or just before to preserve potency and terpenes.
Only reason i have read to leave them for extended dark period is ot can take 24 hrs for the carbs in the plant to settle back down into the roots. Which theoretically would give smoother smoke sooner.