If you please consider the following sequence of spins (the most boring session in your life!)

We bet Before Last and Reversed

1. R
2. R
Bet 1: BL - R, RBL - B

3. R
W/L: BL 1W 0L, RBL 0W 1L
Bet 2: BL - R, RBL - B

4. R
W/L: BL 2W 0L, RBL 0W 2L
Bet 3: BL - R, RBL - B

5. Zero
W/L: BL 2W 1L, RBL 0W 3L
Bet 4: BL - R, RBL - B

6. R
W/L: BL 3W 1L, RBL 0W 4L
No bets as Before Last is zero

7. Zero
W/L: BL 3W 1L, RBL 0W 4L
Bet 5: BL - R, RBL - B

8. R
W/L: BL 4W 1L, RBL 0W 5L
No bets as Before Last is zero

9. Zero
W/L: BL 4W 1L, RBL 0W 5L
Bet 6: BL - R, RBL - B

10. R
W/L: BL 5W 1L, RBL 0W 6L
No bets as Before Last is zero

11. R
W/L: BL 5W 1L, RBL 0W 6L
Bet 7: BL - R, RBL - B

12. R (again!)
W/L: BL 6W 1L, RBL 0W 6L


So, Paul; as you see here we had a TOTAL of 3 zeros (9,731 in the files) and therefore a total of 7 bets (352,288 in the files) = (12 - 2) possible bets - 3 zeros where no bets were made. But as you can see; the "difference" between the two systems is only 1: namely the one loss for both at spin 5. We never lost at the other two zeros. The one zero we lost = 9,448 in the files.

All this would not be, supposing we never had two zeros with one number in between.