Here's the issue: some of the players in my group tend to be pragmatic...a little too pragmatic. They are the type who'll figure out the most efficient and cleanest way to take care of any problems, who rather to nuke it from the orbit to play things safe rather than taking on risks.
My current campaign is heroic fantasy, and I have taken pains to emphasis that while it is not 'heroic stupid', the players are to be the heroes. We used the Same Page Tool to ensure we all knew what that meant. However, one or two of the players still frequently come up with brilliant plans that negate them adventuring. For instance, if there is a brigand stronghold in town, the player will rather spread rumours to neighbouring lords that exaggerate the amount of wealth and atrocity of those brigands as to entice them to attack the stronghold, instead of venturing in themselves. And they would suggest heading back for reinforcements and so on.
There are a few reasons why I would rather them not do it. First, it's not about them adventuring any more. Some other people will step into the limelight. Second, in case of reinforcements, it's more combatants and that drag things out. Third, if I say "yes, but," anything I do may come across as vindictive. Fourth, we agreed not to play those kinds of stories.
I have tried, the last time this happens, to say, "Look guys, this isn't the genre of adventure we agree on. Don't do this. I won't enjoy GMing this type of game." but I rather not do that a second time. (Meta-railroading, how low can I go?). Or, how I can accept such solutions, but still keep the PCs in the limelight?
It's not that I don't want creative solutions, but I want to—and we've agreed to—play dramatic stories. The specific kind of creative solution that results in a humdrum "safe" course of action is not a good fit as it doesn't create a dramatic story.
We're playing 13th Age, a narrative-centric variant of d20, which has this topical advice to players about creative solutions:
Create Dramatic Stories
In traditional roleplaying games, players try to invent the smartest, best or most efficient solutions... the worst approach is to come up with the safest solutions... We encourage you to be exciting rather than prudent. When inventing a solution to an open-ended problem, approach the issue the way a good writer approaches a plot point... Think about what would generate fun.
I am also looking for ways to work with the PCs' solutions, as long as they remain the focus of the game. How do I encourage players to contribute drama to the narrative instead of playing it safe all the time?