It's not a theory or opinion...
Your right, in part, but the part your missing is the science, where if the firebox wall itself is cooled to 136 degrees, moisture from the wood can then gather on the walls instead of going out the stack, simply watch your stove on your first fire of the season, she'll sweet like a pig til the water gets up above 140, then it's not possible for water to stick to the steel, but goes out the stack.
The cold water coming back into a larger volume does help it some, but does not fix it. If your return is focused on one spot on the fire box, it allows that spot on the firebox wall to be cool, hence moisture will gather there. The NC I was speaking of, the customer burned quality wood, that was confirmed by his dealer "a friend of mine" but no wood is moisture free
So, as I said, you are right in part that green wood is harder due to the water getting into the Ash, but if the firebox walls were hotter, the moisture couldn't gather and out the stack it would go
If you think that's the reason I think you'd be a fan of maintaining as clean of a firebox as possible