from what ive found the guy was from the 30’s and his thoughts are someting like this
The horse shall win at least one in three races;
The horse shall be placed second, third and where appropriate fourth in at least half of the starts;
The horse shall be entered to run against no similar money consistency horses.
(This key requirement is subject to much interpretation and determines whether you bet.
Additional requirements by Dowst
Only play when the track conditions are fast or good.
Do not play in races where fillies oppose colts;
Do not wager on 2 year old races or flat horses of 6 years plus.
Do not wager on horses raised in class.
Do not wager on horses carrying too much weight.
Not sure if anyone has applied the above and crunched any numbers