All I know is that blizzard stated that they want to make sure that gold has an ingame value, which shouldn't be a problem with the artisan services you have to pay for. Just adjust the costs and the gold drops from monsters and done.
As long as gold has a value the GAH makes sense.
How exactly you are going to make your "ingame living" is up to you.
I don't think they will be able to adjust it on the fly at least in terms of making it more scarce - I think we'd notice if one day a certain monster drop is 50-60 gold and the next day it's 10-20 - that would be a case of moving the goal posts after people have already achieved certain goals (the rich/accomplished would have a huge advantage of already having leveled their crafters when gold was "easy")
I think it would be better to crank the dial over to "Ebeneezer Scrooge Stingy" on the gold drops and keep it there until people can barely afford to repair their gear then slowly increase drops until the economy stabilizes.
My guess is that it won't truely be dialed in until the expansion when they will have exact ideas about how large a gold sink has to be to maintain a characters progression/leveling/crafting needs on a server wide basis.