After running my players through slightly modified versions of three pre-written dungeons (the Blue Box Basic introductory scenario, B2: The Keep on the Borderlands and B1: In Search of the Unknown), I finally wrote up a single page dungeon scenario—a total dungeon crawl with nary a visible trace of Gygaxian naturalism—and ran four of my players through it. They got halfway through the dungeon in their last session and are excited at the prospect of tackling it again!
A few lessons I’ve taken away from the experience of creating and running a small dungeon level:
1) Writing your own boxed text is no substitute for remembering it. I built the first room in the dungeon around a magical trap, then added enough other details—a magic mouth, doors that lock themselves, and monsters emerging from doors masked by illusions—that I forgot to deploy the trap! I wound up relocating the trap to another room, so the idea wasn’t wasted, but there wouldn’t have been any problems if I’d written my notes in a less florid manner, or simply re-read them more thoroughly before starting play.
2) It’s great to devise unusual phenomena in your dungeon, but you need to think through their effects during the design process. Last session’s dungeon included a maze with invisible walls (credit goes to Infocom’s Sorcerer) which also hid objects behind them. Thus, while you could see the outer (non-invisible) walls of the room, you couldn’t see the monsters stalking around inside the maze. But I didn’t consider that this would also affect the PCs, so that as soon as the party turned a corner, the people at one end of the marching order would be invisible to their fellows!
3) When designing tricks and traps, there’s no sure way to predict a party’s level of caution. The same players can shift from paranoia to recklessness and back again at seemingly random intervals. As a referee, sometimes you just have to roll with the party’s actions and see what happens.
All of these lessons apply to pre-generated dungeons as well, particularly the first. But it’s worth noting that designing the dungeon yourself may not, in and of itself, provide additional insight into the place, nor does designing it with your players in mind assure you that they’ll react like you expect them to.