Back in the day when I played HU Hyper-Turbos on Pokerstars I created one of these in Mathematica (not as fancy with Monte-Carlo)
A similar calculator created many years ago is at https://www.albionresearch.com/tools/kelly
What bet you can make consistently gives you at least 51% odds? As far as I know, the best you can do in a casino is 48%. If I plug 48% into the simulation, it states there is no Kelly edge for that bet.
As far as casino games, you might find yourself in this situation with a half-decent poker hand or if you're counting cards in blackjack. Casinos don't hand out advantages over the house, which is why the former is coming from other players and the latter is against the rules. As the sibling comment notes, it is generally irrational to participate in casino games and the simulator is correct to tell you not to do so.
This comes up more when you have (or at least believe you have) information that the counterparty doesn't have.
The first time I ran across Kelly it was WRT card counting. There is some rare positive off the top video poker out there.
[dead]
Interesting, I recently learned about this.
So there is a term called "Full Kelly" which is were you actually wager the amount given by the formula. This is pretty aggressive and not for the faint of heart. Usually, you do something like a "half Kelly" where you halve the suggested bet amount. Usually because you assume you might be incorrect in your estimated advantage.
What I haven't found yet is some mental math rule to apply this. Given some assumed advantage, what percentage should I "wager"?
Optimal bet size is 2x the coin bias. Dérivation here: https://www.edwardothorp.com/wp-content/uploads/2016/11/TheK...