When you guys are gambling and already doubled your bankroll, do you still play with the whole money you got or you take away half of your bankroll and start playing with your profit or not?
The safety way is play with your profit, because if you lose you still your money left. But if you confident with that bet and want high profit badly, you can go all in, high risk high return. I prefer play with my profit though.
Play using your profit is a good way, as you say, at least when you do not run out of money to lose your principal. Money is more important subject, if you've lost your base currency, then what will you do? to gamble again could not. If you lose your profit, you still can gamble with the money of your principal if you want to.