Goldcoaster,

In my staking a loss wipes out all four series, as it appears to in Testarossa's (jump in at any time Testarossa).

It's just that the multiplier effect of reinvesting winnings well and truly compensates for the times you miss (remember these guys have 80%+ strike rates).

Okay so....
A - Win, B - Win, C - Win , D - Win, E - Lose, F - Win, G - Win

Bets on: A, B, C, D, F, G at level stakes, A*B, B*C, C*D, F*G 2 race parlays, A*B*C, B*C*D 3 race parlays all win.

E, D*E, E*F, C*D*E, D*E*F, E*F*G all lose (each bet started a new series).

So you've bet 18 units (notice that's 3 units per race plus winnings where applicable) with 12 of them collecting. On a six out of seven strike rate (86%) you are almost certainly in front (I gave up guaranteeing anything years ago) but on 5 out of seven your average dividend is going to need to be better I suspect (without doing the maths).

It's up to you now to learn how to use Excel or some other spreadsheet, fire in your historical data and see what suits your strike rate.

Placegetter

PS. Don't forget principles of protecting your capital can still apply too. Just because we are gambling/wagering/betting (as opposed to investing) doesn't mean we can't be smart and grow rich slowly.