is it something simple like:
# Favourite must be ranked in top 4 by prizemoney/race?
# Favourite must not be rising in class and weight?

With sufficient pre-post markets and results, one could check these factors themselves - anyone kept formguides each week this year??
Punters - if you keep either Friday's formguide or saturday each week for 6 months or more - you can do your own testing of simple ideas/systems like this.
Results can be obtained from NSWTAB site or other state sites I guess.