Spin 8: +4,

Spin 9: +3 and

Spin 10: +1 as those figures are keys to understand how this works. Now let's see what happens when we are betting High:

Spin 1: We bet 1 on High.   Decision: 25 High.   We win. Net Result:          +1
Spin 2: We bet 1 on High.   Decision: 10 Low.    We lose. Acc Net Result  : 0
Spin 3: We bet 2 on High.   Decision: 18 Low.    We lose. Acc Net Result:  -2
Spin 4: We bet 4 on High.   Decision: 25 High.   We win.   Acc Net Result: +2
Spin 5: We bet 1 on High.   Decision: 33 High.   We win.   Acc Net Result: +3
Spin 6: We bet 1 on High.   Decision: 7 Low.      We lose.  Acc Net Result: +2
Spin 7: We bet 2 on High.   Decision: 30 High.   We win.   Acc Net Result:  +4
Spin 8: We bet 1 on High.   Decision: 7 Low.      We lose.  Acc Net Result:  +3
Spin 9: We bet 2 on High.   Decision: ZERO!     We lose.  Acc Net Result:  +1
Spin 10: We bet 4 on High. Decision: 29 High.  We win.   Acc Net Result:   +5

(Please note the three last results) This is not a bad ending, is it?  We are 1 unit up on Low and 5 units up on High despite we had a total loss on the Zero.  So it didn't matter which side we were betting; the end result is positive. But what would happen if we bet BOTH sides at the SAME TIME?

Spin 1: Bet 1 Low + 1 High,   Total bet 2. Decision: 25 High.  Win 1, Lose 1.         Net Result: 0
Spin 2: Bet 2 Low + 1 High,   Total bet 3. Decision: 10 Low.   Win 2, Lose 1. Acc Net Result: +1
Spin 3: Bet 1 Low + 2 High,   Total bet 3. Decision: 18 Low.   Win 1, Lose 2. Acc Net Result:  0
Spin 4: Bet 1 Low + 4 High,   Total bet 5. Decision: 25 High.  Win 4, Lose 1. Acc Net Result: +3
Spin 5: Bet 2 Low + 1 High,   Total bet 3. Decision: 33 High.   Win 1, Lose 2. Acc Net Result: +2
Spin 6: Bet 4 Low + 1 High,   Total bet 5. Decision: 7 Low.      Win 4, Lose 1. Acc Net Result: +5
Spin 7: Bet 1 Low + 2 High,   Total bet 3. Decision: 30 High.   Win 2, Lose 1. Acc Net Result: +6
Spin 8: Bet 2 Low + 1 High,   Total bet 3. Decision: 7 Low.      Win 2, Lose 1. Acc Net Result: +7
Spin 9: Bet 1 Low + 2 High,   Total bet 3. Decision: ZERO!     Win 0, Lose 3. Acc Net Result:  +4
Spin 10: Bet 2 Low + 4 High, Total bet 6. Decision: 29 High.  Win 4, Lose 2. Acc Net Result:  +6

If you compare these last three results with the sum of the same results above, you will find that they are exactly the same:

Spin 8: 4 + 3 = 7,

Spin 9: 3 + 1 = 4 and