This humidity thing has led me to the tentative conclusion that I will measure and record the humidity of the powder for each reloading session and the date. It I measure one and it’s an outlier, I don’t know what I will do but probably mix it with another pound as above. Putting a “humidity pack” with my powder seems extreme and untested.
Actually, I'd say it has been tested. If you don't know much about Bryan Litz, check out his history (his education and experience is impressive). Here's what he says is one of the thing they do: