Yeah following VPD can be a gamble, they say if you stick with ideal VPD that you’ll get the best growth and yield. So for a possible 5-10% faster growth and yield you risk losing a good amount of your crop to bud rot or have to deal with powdery mildew, not worth it. I’ll keep all of my buds and not risk it. I’ve never had bud rot indoors or outdoors, I’ve seen plenty of growers chasing VPD that have got bud rot, even experienced growers chasing that elusive few percent of extra yield by sticking with VPD when they don’t have the proper equipment to do it right.
It’s not that VPD is wrong, it’s just not for most home growers. VPD is fine for commerclal/pro growers with all the right equipment in a sealed grow room, air snipers/purifiers to remove mold spores from the air, dehumidifiers to make sure RH doesn’t climb too high, AC to keep temps perfect, added CO2 to make use of the extra humidity, all the controls needed to keep the environment safe to run at higher humidity levels.
Also, I would never put a humidifier in the tent, all that moisture is not good for your light, fans, carbon filter, etc…
Only time I use a humidifier is when I’m drying my harvest, to keep RH at 60 for a nice slow dry, even then it’s not in the tent (I dry in a tent), it’s in the room the tent is in and drawing air from.