How does that differ from the way every market maker deals with informed traders? (Serious question, not a challenge.)

Well, this is merely a hobby interest to me, and it's a been a while since I read 'Dark Pools' but: it's less "using information" to front-run, and more "taking advantage of computational glitches" to jump the queue and get higher priority in the order book.

I have no idea if this is still an issue (doubt it), but it was in the early days of HFT. Anyway, I'm out of my element...'Dark Pools' is a decent read if you're into this stuff.

I like _Dark Pools_ ('kasey_junk recommended it as an antidote to _Flash Boys_) too. For a slightly older but more authoritative nuts-and-bolts explanation, and surprisingly well-written, Larry Harris _Trading and Exchanges_ is basically the _TCP/IP Illustrated_ of money.