The more I read about SE's decision to wait until some time after launch to implement an auction-like system, the more it seems like it -> might <- actually be a good idea.
For the purposes of discussion, I'm using AH to refer to whatever centralized search/sell/buy system SE might put in place whether it's a retainer search, an auction system similar to XI or other MMOs, etc.
The reason SE has given for the delay in implementing an auction is that it would "determine the economy system." A lot of people are interpreting that to mean that if SE had the AH in the game at launch, it would influence the price of goods. That's not the reason they're delaying it. Think about it this way: you're a new player in a new game. Maybe you have previous MMO experience, maybe you don't. After a few hours of adventuring you wind up staring at an inventory jam packed with goofballs and think, "Gee, it would be awfully nice if I could get rid of some of this stuff by selling it to another player and hopefully get more for it than I would from an NPC."
So now, let's suppose the game were to start with an AH already in place. Which option are you going to choose to sell your wares? The centralized system that offers potential buyers the convenience of searching for exactly what they want or browsing from a consolidated list of goods for sale? That same system is the one you could use as a seller to see what the items you have to sell might go for. A very convenient system.
Compare that to the retainer/market ward system. As a potential seller (and especially without an AH), if you wanted to even try to ensure that you were offering competitive prices, you would have to wander the entire ward checking every retainer to see if they are also selling the items you want to sell and if so, for how much. You then have to set up your retainer's bazaar and hope that prospective buyers actually check it. Add to that the fact that from what I'm seeing so far in the game, people would rather farm their own materials than go ward hopping to try and find them for sale.
There's one substantial bonus to crafters with the retainer system, however, that wouldn't work nearly so well if it was shifted to the auction, and that's the ability to repair items other people put up in their retainer's bazaar specifically for that purpose. If your primary interest in the game is crafting, touring the market wards to find items to repair seems like it might actually be an interesting thing to do if for no other reason than a little variety and some gil here and there. If you were to transfer that same sort of concept to an auction where all you had to do was run a search for items flagged for repair (as opposed to sale), it would just be a case of people camping auction windows. Not only would it be less interesting, but it would quickly turn cutthroat.
So on one hand, you've got the market wards which, for general buying and selling, are dreadfully inconvenient and time consuming vs. an auction house with all its fast search and centralized benefits. If the game was released with the auction system in place, the market wards would probably be ghost towns. So by delaying the introduction of an AH system, SE is forcing players at launch to get acquainted with the system, not because of pricing issues but because the incentives for doing so aren't readily apparent to your new player.
Make no mistake, whether the AH system is in the game at launch or not, it's still going to determine the common price of goods. But by getting that first wave of players accustomed to the market wards by offering no other alternative, people entering the game after the AH system is added will be met by players who are better able to explain to them the benefits of the market wards despite the at-a-glance inconvenience. It's not about price, it's about understanding the system.