Dry spot on butt...

I'm no Bill Nye, but I would say yes and no. Condensation, as in just water, no. Condesation in the form of moisture with added smoke (or charcoal "air") would be blacker "soot" or brown creosote that then hardens up (and will flake off when dry).

My theory is year round weather. My theory adds that weather is not an issue, since (with a wind sheild) I am maintaining temps at the dome of 225*, and I suspect the outside "skin" of the WSM is not that much less in temperature. Since water boils off at 212*, condensation alone (water) cannot stay around.

I evidence this with the Bandera. Top of the chamber can be as little as 190. Soot, condesation, whatever will drip down on the food once in a while.

As far as dry spots on the WSM, I've gotten them in both the WSM and the Bandera.

All the time actually. Spray. forget something, open the door 4 minutes later, doesnt even look like you sprayed sometimes.

What I will do when I wrap, spray the crap out of it, but try and put that "dry" spot on the bottem, where you know it will sit in juice for hours (sometimes need to do this on large spares.

This all makes sense to me, but someone is gonna come back and say "squibble" and what I just wrote will seem silly