I'm not an expert by any means, and I've only got about 6 years curing experience. I did learn something the first couple of years, which is counter to what most seem to be doing to their tobacco. Do not mist or spray your leaf.
Spray or misting leaf creates a wet spot, and in a warm moist environment, you will get mold on that spot. A lot of growers get lucky, in that the air is probably dry enough that the wet spots dries and/or the moisture dissipates to the remaining leaf.
The only safe way to bring leaf into case, and not get mold, is to place the leaf in an adequate or high humidity space. Tobacco is very hydroscopic, will freely absorb moisture from the air. Proper air flow, RH and temp control will keep or get tobacco moist, whether for storage or kilning. It's an art, not science. All the data & research is great, as a guide. But all need to learn what works for them, based what they're working with, environment and tools.
I haven't checked all the above references, but my prior readings indicate that none of the commercial growers directly wet or spray their leaf. they add moisture to the environment.
We are more than a year from the date of Lefty's post above, I am re-reading my thread and wanted to add comment to Lefty's post.
From what I have learned he is 100% correct however, I believe it comes down to how you mist the tobacco. If done uniform and lightly then allowing the tobacco to absorb the moisture (10 t0 24 hours) and then repeating to reach the desired level of moisture while keeping in mind temperature you can avoid mold. The object is to reach a level of moisture that is uniform across all leave with out getting areas that are to wet as suggested by deluxestogie in post number 17 of this thread.
A real example:
My latest video addition to this thread I am misting tobacco to bring the moisture up for kilning. But how did I get the tobacco to the state of condition as seen in the video? Background - the tobacco seen in the video came from a 50 pond pressed bail that has set in my basement for the last 2 years give or take a bit. So this tobacco was very dry and in a bail, if you try to separate the leaves you will destroy them the tobacco needs to be conditioned first.
I placed the bail in my kiln untied the strings and removed the cardboard, set my crock pot - controlled by a PID (the same one that controls my griddle for kilning), set temperature to 98F, and then waited a day. In these conditions the ceiling and walls of my kiln will sweat creating the possibility of some leaves to get way to wet promoting mold, attention must be paid. After the day (about 24 hours) had passed I removed leaves that could be handled, unfolding and straightening them placing them in a stack. Some leaves will have more moisture than others that is OK I know that when placed in the tub with lid they will balance. I then checked the bail to split and open it a bit so moisture could reach inner sections and then let another day pass, repeating the process. On day 3 there was a little blue white mold in an area at the wall near the door about 5 inches square on the surface, I removed it, and checked for more. I found none, but knew I must get this process finished or suffer great loss, I also know Black Mold can begin to invade the leaves at this point. Out came the misting bottle, after the 3 days I could move tobacco around without causing to much damage, getting moisture to leaves that were to dry to work with. The leaves that had been removed to this point were in tubes at a medium case so there is not to much chance that they could mold (yet). I now know time is short and give the tobacco 6 hours and return to remove the balance from the kiln. The job was complete at 11:00 PM.. Next morning I remove the leaves from the tubs placing them back in the tubs in layers lightly misting each layer and wait half a day. This brings us to the stage seen in the video, getting the leaves to a high case for aging in the kiln.
The above is simply to point out, the feel of tobacco must be learned, mold conditions must be learned, the art of creating great smoking tobacco must be learned. To truly know with real understanding you must DO expecting some loss as your price for the education gained.
From what I have learned and I have much to learn yet, LeftyRighty is absolutely correct, deluxestogie is also 100% correct (post #17)