Used to skip it for the same reason. My deck got this gross gray-green tint though, like old moss. The brightener pulled that right out before I sealed it. Now the stain looks even and fresh, not just painted over dirt. It bought me an extra season before it started to fade again.

Ugh, watching that would make my eye twitch. My neighbor hired a guy to repoint his chimney who used a mix so wet it was basically gray paint. It washed out in the first good rain, left streaks all down the brick. The guy tried to say it was a "weathering issue.

My old three pound tent saved my butt in a Colorado hailstorm.