Or flip this around: instead of telling me how HFTs can't arbitrage their trades, tell me what's actually happening. Because HFT's like deepwater oil drilling: it's an awfully expensive hobby to be doing if there's no profit in it. Where's the profit? And who's that coming from? Because in the world of the financial market, it is a zero-sum game, where one set of traders extracting value means another set isn't getting it. It's not as if they're building widgets for a value-added proposition.
I've seen the HFT trade price-seeking patterns -- bandsaw and crop circle visualizations from NANEX (this is now a few years old, so ancient history, but):
http://www.nanex.net/FlashCrash/CCircleDay.html
The point is that by being able to generate thousands or millions of buy/sell orders, across a band of price points, the HFT is getting in on any movement faster than any slower trader.
You're also not addressing straight out fraud where book is open, which is what I understand queue jumping to be. It's one thing if everyone's playing by the rules. Something tells me that's not the case. Oh yeah. That's my former officemate doing time at Club Fed for insider trading.
What's the mechanism for matching buyers and sellers?
Does HFT provide a benefit to the HF trader? If so, from whom does that advantage accrue?
What's the net effect on a non-HFT buyer with and without the presence of HFT? For market orders? For limit orders?
What's the net effect on a non-HFT seller with and without the presence of HFT? For market orders? For limit orders?
HFT provides liquidity to all other traders, including other HFT. They are paid in either the bid-ask spread (in the case that HFT is passive) or arbitrating bid-ask spreads between different exchanges, e.g. they aggress and take out an offer on exchange A which is below the bid on exchange B, providing liquidity to the standing offer on exchange A immediately instead of letting the prices disjoin.
The answer to the last two lines are the same -- there is no meaningful difference between a buy and a sell. The net effect is more liquidity than without any short term market making, for both market and limit orders (IMO market orders should simply not exist, but that's a small aside).
http://online.wsj.com/news/articles/SB1000087239639044398920...
Relevant quote: "He became convinced exchanges were providing such an edge after he says he was offered one himself when he ran a high-speed trading firm—a way to place orders that can be filled ahead of others placed earlier. The key: a kind of order called "Hide Not Slide."
Whether it is legal is highly questionable but it appears that exchanges indeed offer this feature to sophisticated traders.
That aside, Hide not Slide orders are an interesting case. They exist only in US equity markets, and they're a great study in unintended consequences. US equities are quite fragmented (the same security can be traded on several different exchanges), so well intentioned US regulators introduced something called the NBBO (National Best Bid Offer), ostensibly to "protect investors" from getting a worse price on one exchange. What this meant is that different exchanges trading in the same product could never be "locked" - you could never have one exchange showing say 101 on the bid when another has 101 on the ask (because in theory then they are crossed and should trade). Pretend the tick size is 1 for following discussion...
This leads to a situation where every equity exchange in the US may be trading 100/102 (with an empty tick in the middle), but as long as one remaining exchange is trading 100/101, you aren't allowed to insert a bid at 101 on the other exchanges (since the interpretation of the rule is that this would be unfair on the resting 101 offer). But HFTs are all very keen to be the first to fill that 100/102 gap in the spread - to be the first on that new queue is an advantage since you get filled first. And obviously that one holdout exchange will soon get filled and the price will tick up. But the other exchanges legally can't accept a bid at 101 yet.
So exchanges started to either reject orders or "slide" them - you submit that 101 Buy and they slide it down to a 100 Buy. Which leads to this:
10 SUBMIT BUY@101
20 IF RESPONSE = "SLIDE TO 100" THEN DELETE, GOTO 10
All of a sudden the exchanges are being flooded with messages, as algos are pinging the exchange constantly wanting to put that 101 bid in. Which leads us to 'Hide not slide' - the exchanges promise to sit on your order until the NBBO ticks up and put it in the queue then. The problem is that these order types, while documented and available to all who are connected to the exchange directly, aren't usually going to be available to someone who is trading through an intermediary - a broker or some retail trading platform. So that's the story of how a well intentioned bit of regulation ended up disadvantaging US investors.
US equity markets are full of weird quirks like this, the NBBO needs to be done away with.