I would like to see at least some improvisational tips taken from improv acting in the PHB or DMG. I think they are exceedingly useful techniques for roleplaying games.
In the D&D 4e DMG, there was a section on saying "Yes, and..." which comes from improvisational theater. It read:
[sblock]"One of the cornerstones of improvisational theater technique is called “Yes, and . . .” It’s based on the idea that an actor takes whatever the other actor gives and builds on that.
That’s your job as well. As often as possible, take what the players give you and build on it. If they do something unexpected, run with it. Take it and weave it back into your story without railroading them into a fixed plotline.
For example, your characters are searching for a lich who has been sending wave after wave of minions at them. One of the players asks if the town they are in has a guild of wizards or some other place where wizards might gather. The reasoning goes that such a place would have records or histories that mention this lich’s activities in the past, when the lich was still a living wizard. That wasn’t a possibility you’d anticipated, and you don’t have anything prepared for it.
Many DMs, at this point, would say, “No, there’s no wizards’ guild here.”
What a loss! The players end up frustrated, trying to come up with some other course of action. even worse, you’ve set limits to your own campaign. You’ve decided that this particular town has no association of wizards, which could serve as a great adventure hook later in your campaign.
When you say yes, you open more possibilities. Imagine you say there is a wizards’ guild. You can select wizards’ names from your prepared lists. You could pull together a skill challenge encounter you have half-prepared and set it up as the encounter that the PCs need to overcome in order to gain access to the wizards’ records. You could use a mini-dungeon map to depict the wizards’ library if the PCs decide to sneak in, and then scrape together an encounter with a golem or some other guardian. Take a look at your campaign lists, think about what would help the PCs find the lich, and tell the players they find that information after much digging through the wizards’ records.
Instead of cutting off possibilities, you’ve made your campaign richer, and instead of frustrating your players, you’ve rewarded them for thinking in creative and unexpected ways. Make a note of the things you just invented about this wizards’ cabal (adding them to your campaign lists), and use the cabal again later in
your campaign. Everyone’s happy![/sblock]
While that advice was aimed at the DM, I think it's very good advice for the players as well and encouragement to use "Yes, and..." is part of my Table Rules document in every campaign. It cuts down on game-delaying debates and fosters an environment where everyone's good-faith ideas are accepted rather than criticized or dismissed.
Another thing from improv that I think works very well in D&D is the general rule of not asking questions. In improv, you generally don't ask questions when performing a scene unless that question adds new information in the asking (not because of whatever answer might be offered). This is because you're essentially forcing the responsibility of establishing the scene on someone else instead of truly collaborating to build something from nothing.
In D&D, questions are a form of playing it safe since questions aren't actions and actions can sometimes come with risk. So it's a very safe tactic indeed to just ask questions of the DM rather than actually have your character do anything. Outside of clarifying something that the player misunderstood or that I could have done a better job establishing, I see asking questions as a form of cheating in a sense and redirect questions back to the players: "What do you DO to get that information?" I've seen other DMs take a question as a form of action declaration, assuming what the PC does to get the info the player wants. I think this is a mistake since the players declare the characters' actions, not the DM. Some guidance from improv theater to the player in this regard might help improve some common game issues that I've seen.