That author seems to think that this was okay behaviour by Barclays, because the clients had choices and could think for themselves(ie caveat emptor) I do not

That author seems to think that this was okay behaviour by Barclays, because the clients had choices and could think for themselves(ie caveat emptor) I do not see how lying to your clients about the type of pool you have is ok. If it is necessary to have some HFT operators in your pool then do not be a chicken and come out and say so. Is honesty not the best policy anymore? You can be getting the best deals(fills in this case) and still feel like getting a bad deal. It is human psychology. Let's say you find the best deal on a specific car for $10,000. Dealer claims that you are not paying any dealer markup over retail. However, later you find out that there was a special promotion from manufacturer, where dealer got the cars for $1,000. Even though you realize this was not something you could get yourself you would still feel miffed that you were not given a larger discount. I admit my example doesn't have very realistic numbers.