The 2 things I gathered from this is temp and RH. When drying. I spoke briefly about this on another post. 15 years and I'm still learning sht. I don't think that ever stops.

ive never had hay smell. for me it always goes away. i just do the mason jars. Sometimes with 2 way Bovedas and sometimes not. im more worried about the ammonia smell and that comes from jarring up partially dry/wet weed

Bovedas work great, but only in small amounts. I think it’s one pack per ounce. I hang openly in my garage. Oscillating fan at a medium distance, and I’m golden. I get different climates means different ways, but I’m in Ohio. It’s always some kind of shit weather here. Humidity gets bad in the summer so I can’t grow outside due to bud rot. I use the bucket curing method. It works best for me.

I didn't quite understand the difference between drying to fast, and not drying enough. I guess both factors result in the same prob.  I do agree though, that the hay smell comes from several different things, all of which they covered. Good vid !!

For me, once in jars, they get opened 2 or 3 times a day for the first week. The it starts dropping down has the smell gets better. Then just now and then. Never really had a hay smell.