I think, Martiangle is a good strategy but very dangerous if used constantly, I've lost 1 BTC because this strategy.
Actually, I never succeeded, Martiangle strategy is not good as the theory revealed. The practice is totally another story.
It works if you have enough money and start with very low bets. Sadly, I think some sites employ scripts that prevent you from abusing martingale, that's why some people recommend to change "seeds" from time to time if you run into a wall of losses.
Otherwise people would just go in with a high amount of money, like 100BTC, set the minimum bet to 0.001BTC and run on auto 24/7.