I emphatically agree that less is more. HMS Iron Duke was Admiral Jellicoe's Grand Fleet flagship throughout most of the war, and was considered as a "showboat" throughout most of her subsequent career. As such, she was very well maintained; I suspect there was little to no apparent rust.
Many modelers tend to over-do weathering on warships, making them appear as little more than unkempt skows. Washes can be too heavy, rust can be over-emphasized, and salt staining renders the ship a gigantic salt lick. Less is definately more!
Bill Morrison