There's no way that paint could absorb a pint of water.
Think of it this way. You wash an unwaxed medium sized car and afterwards there is coating of water on the surface. If you gathered all that water together into a container, it might make about a pint. There is no way the paint system could absorb the same amount of water, even the most oxidized chalky piece of work you can find.
Now if you were talking about a stretch limousine, I might understand.... but then the argument becomes relative to the size of the car, which is not mentioned in Ketch's post.
He is a great guy though and I also have learned a lot from him in the past about detailing. Logically, on this point, I would disagree. There are too many other factors that need to be mentioned before making a sweeping statement like that, IMO, like surface area, temperature, water composition, etc.
Tnx.
Xill.