From what I understand, if a user 'buys' a stock on the platform and its price goes up, he will have more MPH, while the price going down will lose him MPH.
This system seems to work well as long as the volume of correct bets don't surpass the volume of wrong bets.
What happens if users buy large amounts of stocks that go up by a large margin, if the number of winners on the platform become disproportional? It seems the MPH supply will extend by a vast percentage, but there is no mechanism that would make the token price itself reflect the correct bets of the platform's userbase. So the winners that liquidate their stacks late may very well still be at loss, should they wish to claim their earnings in anything other than MPH.