I don't think you had it adjusted correctly.

When you adjust it you can use it a couple different ways.

One is to help it diffuse overly harsh lighting...stopping down qworks better in this matter or just waiting for the light to pass.

Another is to turn it until the blues are really crisp and blue....this usually means you have a decent overall exposure with crisp colors...but you can't stop glare.

Another way to use it is to help eliminate shadows on photos of cars...turn it until you can either hardly see them or in some cases they dissappear, works for glass reflections as well.

Leave it on for daytime shots, it can be a very good friend to you. Ditch it for night shots though since its just a nuisance at at that point.