I don't have this problem as I do all my back checking on the computer - I adjust my criteria and it applies that criteria and gives me the result - therefore I don't manually include or exclude marginal calls. Of course when I am placing my bets I do have the option to override the system but I am learning not to! Have had several instances where I missed out on big collects because the system told me to bet but I thought the horse had no chance only to see it come in.

With regards to adjusting the system I am constantly reviewing it but am finding that the changes I am making are really now just very minor fine tuning.

My system is not trying to pick the winner in every race - simply identify horses that are good value (eg. $15 when they should be $10). I am finding that my "rigid rules" are actually surprisingly good at identifying those horses (better than I expected actually). Therefore it doesn't matter that no two races are ever the same - as long as there are value horses in the field that are mispriced on the tote I will be on the right road!