Well, in my campaign, I use to be very flexible. I mean, the player can do anything they want. To give you a good example of that. One day, they felt very stupid. They were prisonner into a dungeon. A powerful mage had betray them and teleport them into his personnale prison. Eventually, another player who was playing a powerful barbarian/ranger/fighter ( POWER GAMER ... with a good background, though ) sneaked in and freed them. To escape the place. They had to bypass an alarm system and to play on the diversion. I planned they would follow the ranger who actually know the safer way to exit the place without attracting the 350 vilains in the place. Unfortunately, they didn't do as I think they would, and they decided to explore the place, when they exactly knew they were overwhelmed by the ennemy, The ranger player protested, but you know how sun elf can be arrogant and mean toward half-elves , furthermore when the player are playing it stupidly... Anyway, they were eventually capture again, this time with no chance of escape, and I the mage sent them into a Zhent gladiator arena. The point, actually, is that most of my player were very stupid ( at a very disturbing point, I mean when the player let run a guard between two levels so he can alert all of his 100 fellow sleeping at this level, there is indeed a big problem and when they leave only one person to back them off from them ... hum ! ). If my campaign was set into stones, I could have arrange myself to push them into the right way, but it wasn't the case. And I think it's a good thing. Next time, they will think twice before fighting 350 enemies rather than running out for the exit....