Good link. I was writing a reply to make a couple of points but the page says it best: "Many people will tell you to bet less than the Kelly formula says to be

Good link. I was writing a reply to make a couple of points but the page says it best: "Many people will tell you to bet less than the Kelly formula says to bet. Two reasons are generally given for this. The first is that gamblers tend to overestimate their odds of winning and so will naturally overbet. Betting less than the Kelly amount corrects for this. The other is that the Kelly formula leads to extreme volatility, and you should underbet to limit the chance of being badly down for unacceptably long stretches." The volatility is huge; you have a 50% chance of losing half your bank over time even if you bet correctly. Not many people can cope with those spikes in gains and losses!