But it doesn't matter if he is well disciplined in the sense that one week only gambling $20 or below stays at that limit then I consider it still a normal limit.
Setting that kind of limit is actually good. As long as the amount is affordable and within the threshold, it is good.
Newbies forget that once they have enjoyed gambling and they become fiercer as they get more bets.
And upon results, when they are in most losses, they cannot let it pass so they become aggressive.
Yeah, it is absolutely a good thing to set limit to what or how much money we spend on gambling on weekly basis, but this is also for those who earn on daily or weekly basis, those who earn monthly should set out an amount of money they take out from their salary on monthly basis which is channeled towards their gambling escapade, if anyone can do this and discipline themselves hard enough to not stop on the way, then such one (we can say), will possibly do very well in life generally, not just in the area of gambling.
And speaking of such person deviating from their plan due to loses they want to chase, I would say that any one who set such a target as the above for him or her self, but allow him or her self to fall off due to loses, such one is not yet ready, for it is often said that the storm is what makes great sailors, people don't become great at sailing a ship by mere wishing, or by sailing on smooth waters alone, but it's when a heavy storm hit, and they are able to keep the ship from sinking, that is what makes them great sailors.
A gambler who set a target, and does not lose money, will never understand what discipline truly mean.