but when the bankroll grows or decreases my stake in the bankroll also changes, so you are telling me that if I had invested when the bankroll was at 100 btc profit and now it is 2.2k btc profit I would have 22x my investment?
No. You're confusing a few concepts. If you were invested in the bankroll when it was 100 BTC, and then it grew to 2.2k BTC
purely by profits -- then you would've made 22x. But that's not really what's happened. It's best to look at it individually:
* A player loses X btc:
The bankroll will increase by (0.9975*X), but all investors will have the same % ownership (stake) as they did. (e.g. They own the same amount of a bankroll that just increased). Note: how the bankroll increased by slightly less than the player lost (that's cause Daniel is pocketing some money as commissions)
* A player wins X btc with a bet of Y:
The bankroll will decrease by (X + 0.0025*Y), but all investors will have the same % ownership (stake) as they did. (e.g. They own the same amount of a bankroll that just shrunk)
* An investors divests X btc:
The investor is given X btc. The bankroll decreases by X btc. Each investor's stake is adjusted such that (stake*bankroll) is exactly equivalent to before the divestment (e.g. So they now own more of a smaller bankroll) with the exception of the investor who divested, whose (stake*bankroll) will be X less than before.
* An investor invests X btc:
The investor loses X btc from their balance. The bankroll goes up by 0.98*X btc. The person who invested stake is adjusted such that (stake*bankroll) is 0.98*X higher than it was before. All other investors have their stake adjusted such that (stake*bankroll) is the same before. After this process is completed, the bankroll is increased another 0.02*X. (this process is known as the "dilution fee" and is basically new investors paying the old investors (and themselves) compensation for lowering their stake