I'm not sure they hired any professionals to give them insight on how economics works, though I do believe they've been monitoring activity on the AH, how much people buy, how much people spend, how much gold an average player has, how much they use on gear, what kinds of gear and items they typically buy, and how the AH as a whole has caused most players to be shoppers/bargain hunters more often than actual players.
I quote this piece of the Dev Q&A answers all the time, but it really makes the most sense....
Travis: Making the new crafted items account bound was done for one very distinct reason: to give players more incentives to play the game rather than the Auction House. Something we discuss frequently is how the Auction House has impacted the game and how we can refocus players away from farming the Auction House and onto farming monsters.
People want all the gold they can get, because gold can get you the best items in the game the fastest. Problem is...that's the biggest part of what's wrong with this game...or, at the very least, how many people are abusing that fact.
So while I doubt they've hired economics experts to tell them the best ways to stimulate the economy, I don't have any doubt that they're taking the right steps to make the game better. The AH should be a sidebar...it should be a way to supplement gold and gear.
When it's your primary source of both? You're not playing the game the way it was meant to be played. That simple.