I've never seen such dogma around any aspsect of pipe smoking as moisture of the tobacco. I had a guy send me a sample of something and included a note about how idiotic it would be to dry the sample further, because the sample was perfect. It was perfectly moist enough to bite my tongue. If someone wants to smoke tobacco at some scientific moisture level using scientific measureing devices, go at it, buddy. If that someone wants to try to dictate what is "correct" to someone, then they can just insert their ideas up their...
Everyone is different. Different acidty, chemical makeup. And, we live in different environments. There is no way that there can be just one perfect moisture level for everyone across the world. Plus, how borring would that be? We can suggest moisture levels that might work for someone that works for us, but we can't "tell" someone what is the perfect moisture level. It's a subtle use of words that makes something either a suggestion or a demand.
That said, moisture in the pipe has very little to do with the moisture of the tobacco, (sorry) some but not as mich as you'd think. There is ambient condensation, which in Alabama is sometimes 90+%. But, even in the desert, with bone dry tobacco, you will get moisture. The natural bi-product of combustion is water, so the smart people tell me. Smart folks have also explained to me that bent pipes condense more of the moisture out of the smoke than straights. As I understand it, the bend creates turbulence, as does open chambers in the pipe, like where a filter would go or a poorly designed fit for a tennon. The bend works like the tubing in an air compressor, or the condensation tubes on an alcahol still. It pulls the moisture from smoke, whether the tobacco was bone dry or the humidity is nil. Sorry, there's just always going to be some moisture in smoke.
For me, I find that a very slow long draw in my slow cadence produces less turbulence and less juice, moisture, or gurgle. And, straight to semi bends without chambers or poorly fit stems tend to be the easiest to smoke. That's me, some have said the opposite. Do your own research, and find what is best for your smoking style.
Now, I am in the almost bone dry camp. I have smoked hundreds of thousands of bowls at this point in my pipe smoking; wet, goopy, old, fresh, medium, dry, and crunchy. It may piss some people off for some narcasistic reason, but there are some blends and flakes that I taste way more flavor in and get a better burn, when the tobacco is close to crunchy. Not all, but some. Why does this trigger some people? It doesn't bother me when someone has to compare and match their tobacco to a cat turd's moisture before they smoke it. Someone can drench their tobacvo in PG for all I care. I'm not affected (effected?) at all. I am enthralled with the idea people are different than me and different from each other. This is one of the magnificent mysteries of the world. I not only tolerate it, but I embrace it. I'm more concerned when this bothers someone. I wouldn't want to be surrounded by copies of myself.
Anyways, enjoy what you smoke, and smoke what you enjoy. And, maybe try different things if you're so inclined. YMMV