Ed Greenwood provides a great variety of hooks and plots that will take the adventurers into his mega-dungeon by one entrance or another. One of the hooks depends on the players seeing a ghostly knight. I mean, this is hardly a spoiler because it's so bleeding obvious what you're supposed to do. But after the apparition is described, we read:
If the players elect to do nothing about the Ghost Knight, they will soon be unable to sleep - whenever they close their eyes, they will see his angry-faced, shining image coming toward them with sword drawn.That last sentence is particularly rich. It conjures up a scene of human defiance and petty authority worthy of Kafka. Or Looney Tunes.
This vision continues regardless of spells, magical barriers or cures, planar travels, and so on, until the sleepless, exhausted PCs lay the Ghost Knight to rest by revisiting the alleyway in which he disappeared. (Undermountain Adventures, Greenwood, p. 2)
Players: "Okay, well, we're pretty sick of these hauntings, so we're going to burn this plane shift scroll and travel to the Happy Hunting Grounds."
DM: "You spend the day marveling at the abundance of buffalo and opossum. But when you lay down your head to rest in a stand of pawpaw trees ... yes, this low-level knight ghost, this one-shot clue to a secret alley entrance, relentlessly reaches across the gulfs of space, time and probability to wail 'Whyyyy wonnnnt yoooou plaaay with meeee?' all night long!"
Well, OK, this was 20 years ago, in TSR's golden age of plot railroading. It's a sign of how pervasive the one-track adventure mentality was in those days that Greenwood feels compelled to screw over the players' free will even when there is absolutely no need. It's not like the players are following the hook to an adventure that took their DM two months to prepare, or even to a one-track purchased module. No, this is a boxed set that details at least a dozen entrances to the sprawling Undermountain complex. In modern terms, it's a sandbox ... with a railroad running right through it.
And did I mention the Ghost Knight is bleeding obvious? If your players turn down the hook of their own free will, it's like they're telling you, "Nah, we don't really want a dungeon adventure today, do you have something more in the line of a ship's chandlery economic simulation?"
There's a larger lesson here. It's inconceivable today that one of the top RPG designers could manhandle players with a design choice like this. The reason? Language. Over the course of the last two decades, writing about RPGs has reached a high critical level, spurred on by the emergence of White Wolf as a challenger to the hegemony and outlook of D&D, and by the spread of independent criticism over the Internet. Sure, the language sometimes collapses into jargon. But it also gives us powerful tools to articulate what wasn't obvious twenty years ago, let us spot the railroad in a sandbox, and figure out why it's not just an asshat move by the DM but actually unnecessary.