Of course he is a prolific and successful ball python breeder.. at it for decades. He made a youtube video recently saying he is absolutely never concerned with nor does he do anything generally for humidity. It got a little hazy because he said "the only reason I'd be worried about humidity is shedding issues." He didn't mention if he does anything during shedding to up the humidity. He said something to the effect of "bacteria needs heat and humidity to thrive, why would you want to keep your snakes on what will become a virtual petri dish through your combining heat and humidity?"
So what do people think? He isn't the first person I've heard/seen say something similar. Then you'll also get people who say they need 60+ % all the time, not just when in shed.
I talked to one breeder who said anywhere from 40-75%. Like what?? 40-75% ? That's a huge range.

I've also seen it said that too low of a humidity can cause respiratory infections, but others say only low temperatures cause respiratory infections and humidity is irrelevant.

Would be nice to have some clear answers? Any definitive sources?