GMMichael
Guide of Modos
This is what's wrong with published adventures. They have limits, just like the video games do. The GMs, in theory, don't.Perhaps unintentionally, you've just captured the thing that is wrong with so many modern published adventures. . . And, indeed, present the various NPC factions in a more-or-less standalone fashion so that if the PCs go well off the beaten track the GM is equipped to improvise. But, alas, all that takes space, and limits what a 64-page adventure can contain.)
Railroading isn't always wrong.Because of the need of the story, players can't be allowed to choose, because if they are then they might make the 'wrong' choice. So, they get railroaded into the 'right' choice.
If you're using event-based or time-based encounters, you can use the same good story regardless of where the PCs go. If you're using location-based encounters, you can use the same good story regardless of when and why the PCs go.The better way to structure this is to provide a good story if the player flanks right (he gets the epic helicopter shootout and the comrade-death scene), and a different good story if the player flanks left (perhaps his own right wing collapses and his love interest is captured, or some such). That way you get a good story either way, but you still get meaningful choice.
However, a good story isn't always easy to make up on the fly. This is one reason to have an interesting plot.