Vic from Hollywood,
Thanks for the response. I believe you that your software is capable of rejecting a line that moves against the player but even then I am not convinced it is happening in all cases.
My current theory about your lines is the following:
Whenever a line changes there is a brief period (usually about a minute) in which nobody knows about it except people who try to make a bet. For everyone else, it will not appear on the lines screen even if they refresh it. During this time your system employs selection against the player. After the minute is up, the new lines will appear on the screen for everyone who refreshes and this is when your software becomes "honest" again.
I would like to believe that this is not the case but it's hard to find any other explanation for the following phenomenon:
The average time between my last refresh to placing a bet is about 30 seconds.
The average time between placing a bet and hitting "confirm" is about 6 seconds.
One would expect, therefore, that line changes happen about 5 times as often in the first interval compared to the second, yet for me the ratio has been about 10:1 the other way around.
I am quite sure this is not just my imagination and my sample size (over 100) is most definitely significant. In any case I would really like to hear from anyone who has similar (or contradictory) observations.