JP but it might be stupid please do not flame anyways if somebody had to harvest early( I have seen many many threads) would making the amount of light they get make them be ready faster like making them go from 12/12 to 6/18. Could it trick them into thinking they were gonna die faster than they expected so they try to just finish what they have?
Increasing darkness is something that some growers do at the very end of flowering, for the reasons you are speculating, however that won't work from early on in flowering -- if anything, it could slow down your bud production because you aren't providing enough light energy for the plant to use for building big buds.
Have to agree with toastybiz on this one. You can't screw with plants too much, especially where you're at right now. You need to let your plants do what they do. If you're changing up the light too much, your plants can stroke out and maybe even just give up without the light they want. I mean, try it if you want to, but good luck with that. (Oh, and you're totally not stupid, just trying to get ahead of your plants - I can totally get it.)