If you want to check it on practice, try this: make a thousand rolls strictly following some sophisticated strategy, and then make a thousand completely random rolls after that, and compare the results. Only one condition: your bankroll must be large enough for making those rolls in both cases.
I don't think we need large bankroll for making random rolls because if you're rolling in random then you never need to double your bets which means you may not need big bankroll.
Still, I agree that results from strategy based rolls and random rolls may not show big differences. Because, randomness of gambling may or may not work in favor of us. Even it will work in favor of us, we cannot expect that to be happening all the days and moreover, due to the presence of house-edge, gamblers get lesser chances than houses to be favorable in the environment of randomness.