From what I have read and experienced it does not need to be sit that long since it is already decarbolyxanated big word I know I spelled wrong since it was vaped.
I typically make it before going to do an errand or something and let it sit for at least a few hours to over night. Honestly I cannot tell the difference but the problem is the tincture is always different. I believe it is due to varying quality of abv.
I have had where some drops worked but typically it takes a 1/4 shot or more now.
The tincture is my favorite way of using the ABV but it is not for everyone but for me it is easy and I like the effects though they are not powerful or anything but work well in conjunction with more herb or drinking for me, on its own it is nothing special but I will take it hehe.
If you make please let us know your experience in the thread lo posted
http://www.fuckcombustion.com/viewtopic.php?id=1564 so others may benefit from your experience. Be it good, bad or meh.
Good luck and happy vaping!