You know what, if you ask me, the problem isn't with AH or MW. It's the supply of materials and gil in circulation.

When a rare ingredient for a measly mid-level gear is hard to come by and people start to complain, SE probably should look at adjusting the drop rate, or create another alternative to obtain it, this will place a price ceiling on that ingredient, hence inflation control. They need to keep a very very close eye on item supply.

With the guildleve system in place, gil is easy to come by, not to the extent that everyone can be rich, but it certainly closes the wealth gap. There will be far less complaining about low purchasing power in FFXIV than XI.

Anyways, forcing prices down through an inconvenient and irrational system isn't really an ideal way of price control.