I uploaded some more data today to my website and if you run just favourites (both bet and lay side) you get the following:

There were 49527 horse form lines in the database at this point in time. We update when we get time.
There were 5147 selections for the System
There were 1757 Winners for the System for a strike rate of 34.14%
There were $5165.57 returned for WIN (after 5% commission) which means a Profit or loss of $18.57 or a percentage profit/loss of 0.36%

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The Rules used were : priceRank < 90 and priceRank = 1 and priceLayRank < 90 and priceLayRank = 1

That is showing a 0.36% profit after 5% commission just betting favourites with no filters. Figures taken from 10 secs before scheduled race time and market must be 95%. AUS Markets only.