Ok, after a few sessions, I realised that 84% humid buds producing far darker ABV then vaped on 62%, therefore I assume more trychomes were utilized or been vaporized with higher intensity. I firmly think that increased humidy before vaping is equally increasing the potential of the plant material being vaped. I'd recommend going for a trial on this, but never ever store you buds in 84% RH room temp for more than a day. I don't know the timeframe and the exact factors for mold to grow, but better safe than sorry.
I don't think this is a safe assumption. First, trichomes will be pretty much vaped out with any decent vaporizer producing enough heat and being used properly. Check your ABV under magnification as compared to fresh bud (ground or not). To my eye it usually looks as if all that is left is the "deflated" trichome shell or hull, now an orangish, gold or tan color (if even this). The glistening full bubbles will be gone long before your ABV is too dark. It's not too hard to get to this point and still have pretty green ABV depending on your material, grind and vape.
Second, with the same amount of hits on the same temperature, a drier starting product will almost always leave a darker ABV. I attribute this to the plant matter heating more without moisture to keep it cooler and "roast" slower.
Perhaps you get more hits per load before it becomes unpleasant tasting or closer to combustion with the added moisture? More hits will usually lead to darker ABV, too. The added moisture adds more water vapor in each hit, so you will get more hits, or bigger hits, or both. But, that doesn't change the fact that the additional volume is simply steam with no additional actives. More of a vapor "filler", not unlike the additions of corn meal or cobs to pet foods. Nothing wrong with this. Most mixed drinks have fillers too, they just call them mixers. Personally, I almost always like a mixer in my liquor - but not so much in my vapor. But, could see how this would be beneficial to many for smoothing out hits, reducing throat irritation and stretching a session. Similar to the way I'd rather have my liquor with a mixer for pretty much the same reasons.
FWIW, I store mostly with 62% Boveda packs, then usually dry a bit on a warm surface (cable box, router, stereo amp) before grinding .
I've also found as others have mentioned above that starting with slightly more moist material will often give a better flavor profile on the first couple hits. I've always assumed this is because the added moisture slows the vaping process initially, allowing terpines to be released at a slower rate and prolong flavor. The same results can usually be had with material at the exact same RH (moisture content more accurately), by reducing the temperature a bit. In essence, by adding (or leaving) more moisture content you are reducing the initial vaping temperature without adjusting your vaporizer temperature. Damned near anything with the ability to absorb moisture will heat slower with a higher moisture content. Weed is no exception.
The reason I usually dry a bit more than 62% is that my material vapes more evenly, and I believe I am getting more of the actives and less water vapor (steam) - especially in the first few hits. Sort of like drinking your liquor neat, instead of in a mixed drink.
If you have doubts that the additional moisture is adding more steam, try a moist piece of cotton (or other easily moistened substitute) in your vape. Keep the temp a bit lower than you may for vaping, so you don't get that sometimes awful "band-aid" flavor. You can easily get huge clouds, but they don't do much for you other than sooth your throat. If still doubtful about this, try vaping moist cotton with two different moisture contents and witness the difference in vapor production - and I would assume number of hits before drying out.
More vapor? Yes. Slower vaping? Yes. More actives (or more trichomes utilized)? No, I don't think so. If you find this to be incorrect, let me know! Water is much cheaper and easier to come by than what I usually vape. But, let us know what water you're using. I don't think any I've had in the past has any trichomes or actives in it at all - unless sipped from my bubbler!
All other things being equal, I guess the added moisture could also allow for more efficient vaping depending on how much cloud chasing you are doing. You could have the same clouds, but actually take in less actives in each hit. Assume this would have to lead to less wasted active vapor from large clouds. Certainly less actives exhaled (because less taken in per hit), and possibly better absorption because I think the lungs can absorb water vapor more easily than MJ vapor.