Reinvest in gambling? I'd surely not associate that term with betting, i don't know who these experts are or if there are experts in gambling like you say, but i am sure they do not have any crazy advantage over others like you make it seem. You could go crazy about gambling, try to figure out all the tiny nuances, find crazy strategies to beat the casino, etc, that does not make you an expert, treating gambling like an investment does more harm than good and you'd be lucky not to become an addict.

Don`t believe AI. It isn`t ideal, i catch his mistakes much more often than i want.
I don`t think that i`m Pro, and i can`t calculate correct my percent due to withdrawals, but i mostly made 5+% of monthly bankroll profit. So i think Pro bettors can get 10% profit monthly. Not easily but it is possible.