Let say if you had 20% of your bank given to you in comps ahead of your regular bank (like comp money-just so it isn't directly your money) could you always win with a good method and smart money management. (So even if you lost the 20% you just break even for the session.?)
Most people I would think are going to reply YES!!
But, the truth is that it depends on the amount of 'play' required and the size of your bankroll in relation to the play requirement and the house edge in your game of choice.
For instance lets say you have a $1000 bankroll and I give you an additional $200. Now your total is $1200. I require that you must put in play a total of $5000 before you can cash out any of your bankroll ... including the bonus $200 I gave you. The game I offer you carries a 5% house advantage on all bets placed.
Well in the above scenario you will lose $$$ in the long run. Given the requirements you cant win in the long term even with the extra 20% I gave you to add to your bankroll.
If you change the requirements however you can change the expected results.
So, the answer to the question ... as with most questions ... is "It Depends".
GB