Not 65% for drying! That will absolutely invite mold, IMO/IME, it needs to be <50% for drying. I didn't mean to give the impression that this is what I do for drying, I thought the question was specifically about curing.
After I'd tried the jars and lost about a 1/4lb (which was most of that crop) to mold, I decided to treat it a little bit like cigars, but they need a higher humidity and I thought it felt too wet. Then, reading some others, probably the same kind of old-timers you're talking about, I learned that 60%-65% seems to be the sweet spot for curing and packaging. And the whole reason why I use the bins is because I HATE TRIMMING. I have an old back injury (on the job) and it's caused problems in my hips and I can't sit for more than an hour at a time without having to move.
Not to mention that I am MIND-NUMBINGLY SLOW at trimming. I don't know why, but I am. I cannot tell you how bummed I am that my Trimmer Lady's kids are sick this week. I freely admit it, I am not one of those people who can trim pounds of dried bud in a few hours, the very concept boggles my brain. How do they do it and not cut off their own fingers, or badly fuck up the buds? I don't know, but now I've got me my very own Trimmer Lady and I plan to keep her.
Anyway, after losing all that to mold I got some of those cheap environmental thingies from Lowe's to put in the bins a friend suggested I try, the analog ones for RH and temps, and hang those with a piece of green tape on the inside, near the bottom. Everything is kept in my basement because I can lock it up very securely, plus it's open to the earth (the area I use is built-up subfloor, no finished walls) and that seems to keep a much better RH during summer time. Winter is a different problem, it's raining and so it's too humid down there, and I often have to bring things into the house (again because the basement area is open to the earth), so I have one great big digital environment monitor so I can gauge what's happening in the larger environment, if that makes sense. If I have stuff in the basement curing and the humidity is only a little bit too high, I put them into a wooden container and keep fans moving all around, with lids open or propped open, and I check daily and will carefully turn the branches to ensure no wet or dry spots.
I'm up in the mountains in Cali, so it can get pretty dry during some times of the year, and then the rains come and forget about it, everything's wet except inside where there's fire.