In basically every game I've run or played, regardless of the system, I've encountered the same problem: things that should be quick decisions end up taking ten, twenty or even thirty minutes, and not for any really good reason. Gameplay generally goes something like:
GM: Okay, you're standing on the edge of the forest.
Player 1: Okay, I ready my bow and start forward.
Player 2: Hold on, I'm still talking to this other guy.
Player 3: Did we stock up on bread? I need to put on my night vision goggles.
Player 4: [Crazy roleplaying thing!]
GM: Okay, are you guys going into the forest?
Player 1: I am, yeah.
GM: Okay, but are you going alone? Is anyone else going?
Player 2: One sec, I need to cast detect evil.
GM: Okay, what about everybody else? Is player 1 in the forest by herself? What's happening?
And so on …
Since part of the point of playing roleplaying games is being able to manifest your own character and make your own decisions, it's hard for any one player to enforce a consensus in the group (except in some rare cases), and it's even harder for me as a GM to justify undermining player agency by just saying, "Okay, well you're all in the forest now." What if Player 2 feels cheated because he didn't get to cast detect evil and find the scary monsters? But at the same time, when this kind of hemming and hawing happens constantly, even at not particularly crucial moments, the game really starts to drag, and more action-oriented players start to tune out. So basically, this question has two parts:
As a GM, how can I design adventures to minimize these moments?
How can I move players smoothly past these moments when they do arise?
I'm not interested in answers that use a stopwatch or other artificial method of advancing the game, because I find that breaks immersion. I'm looking for storytelling and facilitation techniques. Pointing out game systems that specifically avoid this is also welcome.
Also, as a corollary, is there anything that individual players can do to help things along?