Higher-than-retail server population creates a lot of currency entering the system every day, but the gold sinks are tuned for a much lower population.
The suggestion here is to add additional gold sinks, where players can purchase in-game things that do not affect game play with in-game gold. The idea is to take gold out of the economy, which should help balance it. These purchasable items could be things that are typically items you get for donating on other servers.
Yes I know that this would require more GM time (a resource we are short of). It probably has to be managed semi-manually. But the benefit would be a better balanced economy and it might be worth it as an alternative to putting patches in that break the Blizzlike nature of parts of the game (e.g. DM North tribute.)