I never thought Martingale method can be used in the game sportsbook, but if you do arbitration it very safe .
Martingale will never go well.
this method already exist in dice. you can adjust your odd to be 1.5x and use the same method. but if you calculate the probability, you will be still in the disadvantage.
Martingale in sports and martingale in dice game is totally different, in dice you dont have control of win , but in sports you can predict if you do analysis and research of game and teams.
I have tried this martingale and won some times, but what above user told about arbitration is correct, in sports going for martingale is better to go for arbitration, like if you are betting for over 2.5 on high odd then when the odd comes to low favrite that time you can take arbitration and in both situation you will be in profit, that is the benefit of sportsbook