Go into a casino and announce that you're going to martingale or use some other progression and start playing. Say you're increasing your bet according to this this and that rule while talking about how great your system is and how you can beat the house.
Go into a casino and start counting out loud and when you increase your bet say "well, true count's at +3, better bet 3 units!" on every index play give the mathematical explanation of why this move is correct.
Now even those that don't believe the math behind it, they would have to believe the casino wouldn't let them play if the casino knew what they were doing and knew they were losing money to them. Granted some places would half shoe you for martingaling since they don't tolerate spreading period but that's pretty rare
Go into a casino and start counting out loud and when you increase your bet say "well, true count's at +3, better bet 3 units!" on every index play give the mathematical explanation of why this move is correct.
Now even those that don't believe the math behind it, they would have to believe the casino wouldn't let them play if the casino knew what they were doing and knew they were losing money to them. Granted some places would half shoe you for martingaling since they don't tolerate spreading period but that's pretty rare