Nice article. Wondering though why trading is not done in discrete batches, e.g. 5 second intervals? Trades in the same interval get filled equally or stochastically? Info about trades with that same 5 second batch delay? Is there some (theoretical) market efficiency thing at play? All this HFT feels wasteful and bad for 'regular' human investors.
If you think about it you can never eliminate the advantage of being faster. If you do 5 seconds batches it just means the edges of the batches become the time-sensitive points. If you want to kill HFT you can do it directly via very very small transaction fees. But guess how popular that is...
You mean you can never completely eliminate the advantage? But mostly eliminating it might still be useful?
Suppose the rule is that if you get your request in by 01:23:45 then it gets handled in the following 5-second period and the response is sent out at 01:23:50. Does someone (A) who finalises their request at 01:23:44.9999 and gets the result back at 01:23:50.0001 have an advantage over someone else (B) who has to finalise their request by 01:23:44.8 and gets their result back at 01:23:50.2? Yes, certainly, but it doesn't seem to be much of an advantage ... So person A can take account of exciting news that arrives at 01:23:44.9, while person B can't, true, but when it comes to reacting to other trades, person A has 4.9998 seconds to think about the news, while person B has 4.6 seconds to think about it, which doesn't seem like a huge difference. Compared to how things work today.