Even without revealing the highest offer, the offers themselves constitute a silent auction, which is where a lot of the information asymmetry comes from. If I could speak to each of the other people and tell them I had X amount to spend we could all agree to walk away or make offers without going through a bunch of hassle and (for 32 of 33 offerers) heartbreak. The process really highlights to me how broken certain types of 'market' can be when there's a monopoly of information.
toomuchtodo: I am not sure if i would call it "true" value. The true value is what you'd get if you were to sell it again. Maybe at that same day, which sounds to me like the runner-up bid.
