AbdulAlhazred
Legend
So, what you are asserting is that the content of the fiction of the campaign in any game is not a function of the material on proffer from the GM, in the form of a module or some other similar form of material that was generated largely or wholly indepedent of the specifics of the PCs being played? I find this assertion to be preposterous, to put it bluntly.If the party can either attack or not attack the bone naga ambassador, in what way are their actions constrained? The book gives you lots of options to use the material, but there is still no requirement that any particular thing happen. As I said before, if the party behavior is quite different than what the author expected, it's going to play differently, and not just because the PCs are willful. All those if-thens are contingencies to keep the party "on track" in terms of using the material in the module, but the existence of all those possibilities is just a tacit admission that you can't make the PCs do any particular thing. I think the mere existence of such guidance shows that the idea PCs will "stick to the module" out of some sense of etiquette is unrealistic, if not meaningless. At the end of the day, a module is just a collection of people, places, and potential events.
I'm very skeptical of the assertion that because published adventures often propose a mostly linear series of events, players are beholden to only do things that have been anticipated by the module writer. I know that I, as a GM, certainly don't invest a lot of energy preparing in such a way that I assume the players will fall in line. One reason I haven't done a lot in terms of publishing modules is that I don't necessarily care for the effort involved in turning a one-page writeup, front and back, into a thirty page adventure suitable for a stranger to run, accounting for and writing out all the contingencies I would deal with intuitively. That a published module has written out some helpful information, forks, and ideas, does not mean you, or the players, are beholden to a specific course of action. It certainly does not mean the GM is restricted to running what's in the module.
I can think of very few actual play experiences I've had that were run this way. Even in organized play experiences, like Adventurer's League, there were very few rules about completing particular sections of content. At one point, I was on a FB group specifically about running a particular hardback adventure series, and there were whole threads about how the PCs interacted with certain NPCs or defined their own goals.
To me, the idea of a bunch of players showing up and thinking they have to "stick to the module," whatever that means, it just makes me feel a little sad. What happened to them in the past, that the spirit of curiosity and adventure was beaten out of them? Anything will stick to the module. Your job is to be interesting.
You're running Phandelver, there will be a mine, a town, a ruin full of goblinoids, a dragon lair, etc. Sure, the players can have their PCs visit them in several different orders (but the mine will always come last and typically the town first). They might even have some options involving whom they fight, I'm not sure as I only played through it, I didn't read it.
Regardless of anything else, the story will revolve around some PCs being hired to find a lost mine. Sure, they can just lark off in some random direction and ignore the entire content of the module, but that's VERY UNLIKELY to happen. Most GMs will probably deploy some in-game social persuasion to get things back on track, maybe even just a flat out appeal to the players at the table to not hose the GM. Some GMs might then go so far as to employ in-game force such that the PCs arrive at an appropriate location (IE by moving them around, making them get lost and stumble upon the location, capture, etc.).
Note that the material and situations bear no relationship to the PCs. There isn't the slightest anticipation that the content of the adventure is sensitive in any way to the PCs BIFTs for example. It is a canned adventure, it just happens how it happens. Sure, RP of your character may bear on what choices you make in terms of which locations to visit and what to do there, but play is ABOUT a story that was pre-authored!
Isn't this FUNDAMENTALLY different from playing, say, Dungeon World, where the GM could well devise the equivalent of Phandelver as an adventure front, but only after session 0, which is going to include elucidating the history and goals of the PCs, from a player perspective, and where the principles dictate that this information should form an important input to the construction of any front, steading, map, etc. That is, the game will be ABOUT the PCs. They are the main characters, the protagonists in the fullest and broadest sense of the term.