They look like past their peak for my preferences, leaving them much longer and they will be dead, to put it bluntly. Leaving them for 3 days in darkness is foolish, after 3 days they will have a virtual zero metabolism, meaning all the terpenes and cannabinoids you have been waiting for will be breaking down rapidly into non psychoactive components and reducing the high of these plants even further. At this stage, right now, they have well and truly passed their peak in THC quality and quantity, and now have plants with more CBD and CBN, giving you a heavy sedating stone, with very little high. You might prefer "couchlock sedation" over "uplifting high", but if in the future you would prefer non drowsy pot, harvest your plants when there are 5-10% of the very last pistils that are still whitish. Waiting until all the pistils have gone brown, is basically one step from the death of the plant. I personally am not in favour of using trichome colour as the sole indication of maturity/ripeness, I have had plants with 65% plus amber trichomes 4 weeks into flowering and base my assessments of maturity on pistil colour, as this gives a true indication of which stage the plant is at biologically. Once all the pistils are brown, the plant is very much past its reproductive peak, meaning THC has also past its peak in quantity and quality. While there are just a few remaining white pistils, the plant still has a fully functioning metabolism that is supporting THC quality and quantity. After this peak, THC breaks down into CBD and CBN, due to the almost stagnant metabolism being unable to continue with THC synthesis faster than what THC is being broken down into CBD and CBN. The result of late picked pot is that THC has diminished and CBD and CBBN have increased and this produces an effect that is heavy, sleepy and uninspiring. Pot harvested earlier, while there are still some whitish pistils remaining, will have trichomes which have a greater quantity of THC, with rising levels of CBD and CBN, meaning pot that is harvested then, will give a more clear, uplifting and motivating experience, without the heavy sleepy effect of cannabis with elevated levels of CBD and CBN. I personally like to get high and be able to stay awake, rather than smoke something that is comatosing and dreary. It is up to you and your preferences, but either way, leaving your plants in extended darkness will further reduce THC levels and degradation of any/all other cannabinoids due to the plants metabolism being virtually stopped, meaning everything will be breaking down, not getting better. Personally, I like to harvest about an hour or two after the plants have woken from their night time sleep, and found through experimenting with harvest timing over the last 35+ years, that this produces pot with the tastiest and most aromatic terpenes. This harvest is done after only one nights "sleep" as would be normally happening, therefore the plant is unaware of what is about to occur and is not under any induced stress, as it would be after 3 days in the dark. I personally would not want to harvest any plant that has been undergoing stress for three days and with a stale and comatosed metabolism. Others may think this is a good idea for whatever reason, but I would much rather harvest an unstressed plant with a functioning metabolism and normal health.
Hope this helps,........ Organoman.