I don’t like wet backs because when you stop for a break, take the pack off, whew! Instant freeze (for cooler days). For hot days, I don’t like wet backs because the sweat will run down the legs and promote chafing. Thus, with the pinnacle or the mariposa, I lay my pack towel on my back. Friction keeps it there. Incredibly, the pack towel draws the sweat off my back and my shirt is practically dry at stops. The towel is soaked. I let it dry in the breeze.
My shirts are usually very thin polly cotton blend that dries quickly. My towel is any towel that dries fast (Cascade, car buffer, etc.,)
May everyone find their sweating zen.