Here is something I found as I was playing with my website:

There were 22459 horse form lines in the database at this point in time.
There were 1561 selections for the System
There were 1294 which Lost (did not win race) for the System for a strike rate of 82.9%
You had to pay out $1381.51 but brought in $1482.95 after 5% commission. This means a Profit or loss of $101.44 or a percentage profit/loss of 6.5%

The rules are :

Win Price < $10
Barrier >= 9
Don Scott Rank >= 2
Bet Type : LAY

Thats a return of 10x the max lay value of $10 and a healthy 6.5% return after over 1500 selections.