Ok - let me take an educated guess at your system:

1. Selection is tote favourite just before jump time.
2. Staking system is a loss chasing system aiming to recover any losses and make a profit with next selection.
3. Either stop after first win for the day or revert back to base bet and keep going (in this case carry forward any losses at end of day to first bet on next day).

There are probably a few additional rules to deal with equal favourites or if favourite is shorter than a cut-off price.

System will always give a profit unless bet size gets out of control before a favourite wins for the day.

If this is roughly correct then the thing you need to work out is how many losing bets can you have before the bet size exceeds your limit and how likely is this to occur. Using a loss-chasing progression on favourites can increase bet size VERY quickly, particularly if you include odds-on favourites (your bet size can more than double with each loser) - from a base bet of $10 you could easily be betting $1000 after a dozen losers. When I did some research on favourites last year I managed to find one day when no favourites won at the 3 TAB meetings run (24 races) - could you withstand a 24 race losing streak?

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