I think the issue lies more in defining exactly and precisely what exactly is not allowed and making everyone (or a majority of people) agree on such rules than the risk of people deliberately breaking these rules to gain an "illegal edge". A lot of these bugs / issues can have grey areas and some players may trigger them even without knowing. Example 1 Taking all of an AIs cities in a peace deal An overflow is triggered which allows you to take all an AI's cities in a peace deal. But what if instead of their cities, you take all their gold / great works? How do you know if you are taking more gold than "you would normally deserve if the overflow was not triggered"? Example 2 Nalanda bug Should we ban every game with this city-state? What if you found out that Nalanda is in your game after T100 and you are having a great game up to that point? Should we ban sending envoys to Nalanda? What if you gain suzerainty after completing easy/unavoidable quests? What if you keep losing/gaining suzerainty, because it is contested by the AI or because it's moving Amani in/out? You can get 1-3-5 or maybe more free techs from actions that are out of your control. This can make a big difference in the end. etc.