One more scenario about this flaw:
lot - 100k without buyout
you make a bid 500k, current price - 105k
1h left: you must to go out and decide to put more, you place 1m
result: current price grows from 105k up to your old bid +5%: 500+5%=525k
your win the lot for 525k. But in case we would have a feature to increase your bid, you would win the lot just for 105k. - you loose money by increasing your own bid: (old bid - current price) + 5%.
If you were going to bid 1 million in the end why didn't you bid that to START with. The same thing keeps being said over and over and over again. You guys are beating a dead horse!
No matter what the situation is, no matter how you spell it, break it down, or try to explain it you are complaining about something that is at the very core of what an auction is in the first place.
1) An auction is NOT meant for you to get a " good deal". An auction is a system that allows a seller to place his goods in the open and allow multiple people to give him bids on what they think it is worth. Obviously there are different perceptions of an item's value, hence there are those who will value an item lower or higher than others.
2) As a seller, you choose the specifics for the auction (buyout, reserve price, etc). Obviously there is no "reserve price" setting in D3 AH but there is a buyout which establishes a ceiling for the auction. The AH also sets a time limit to the auction, ie 1.5 days.
3) As a buyer, you place bid(s) for what you consider to be the value of an auction. The D3 AH requires that bids increment by a specific percentage. Therefore, if you bid more than x where x is the required "minimum bid" you have established a proxy which will bid to your "maximum bid" in the case that others bid on this item. If someone bids above your "maximum bid" then the proxy stops bidding for you. Your maximum bid remains a secret to other bidders as if it were a "silent auction".
4) When the set time limit is reached the auction ends and the highest bidder wins. It doesn't matter how much the bidder's maximum bid was nor what time the bid was placed. All that matters is that person bid the most for the item and, therefore, valued the item at the highest price. The seller's item was sold either via buyout for the ceiling price or (if no buyout) at the highest price placed by bidders in the specified time of the auction.
The exact solution to your above problem is this: bid what you would pay for the item, not what you would like to pay but the exact amount that you value the said item at. No more and no less. The item's value should not change. The stats will stay the same. While other items on the market may become available during the auction, this item is going to stay EXACTLY as it is posted. Therefore, you establish a max value for an item, bid it, and forget about that auction. You have bid what you value the item at (by this I mean bid the max you are willing to pay for the item. If this value is changing that is a problem for YOU not the AH system). If you value it more than others, you will win. If someone else places a higher value on the item, they will win. Stop whining about how you didn't get an item for your bid. An auction is not about getting a 10 million gold item for 400k. It is about how much value each bidder places on an item. Bid what you value the item at. If you don't win the item, someone valued it more than you.
End of story.