I didn't know the role of "steward" existed until I became a lord and then had the option to appoint one, so I can't blame any newbie for failing to ask.
Well if we made it that way I would suggest putting it on the class change page under trader stating that becoming steward will allow them to become trader regardless of their h/p. I personally am in favor of slapping the steward title on knight's signature or just replacing knight of with steward(ess) of blank. I don't why a knight wouldn't include what little title beyond a simple knight he has in his signature.