I've never actually experienced writer's block. I have run out of energy on a novel and had to shelve it. It is still sitting on the shelf, but only because I moved on with other projects and haven't gotten back to it. I have also run out of energy for revising a piece, but I can usually slog through the revision process if I make myself.
Recently, I have been working on two screenplays, and with both I've hit spots where I had to stop. In both cases, it was because the upcoming scenes needed research and thought.
Here's what I've learned about these sorts of "stalls" -- for me these are huge opportunities, because something challenging has caused me to stop and really think hard. Sure, I like it when the ideas and words flow freely, but I've learned to see these difficult spots as opportunities. One of the screenplays, currently titled "Crier" is about a young man who is trying to salvage his family (a brother and sister) and who is also a suspect in a murder that happened next door. Thomas Crier lives with three other young people ages 20 - 26, and their lives are woven together with other friends; so I decided to write an "party scene" that begins with friends showing up for dinner, bringing dishes over to Thomas' house, hanging out, eating, then the party itself, and some kind of dramatic conclusion to the evening, and the morning after. With so many characters and this kind of flow of action, I've having to diagram it, map it, just to get a handle on it; but first I have to determine the subject matter and themes that run through the sequence.
I've noticed that rather than worry and fret when I reach a stalled spot in a story, if I am patient, and if I relax with it for a day or two, and spend time pondering on it and meandering around the possibilities, inevitably the next scene will take shape and it is usually surprisingly good.
Here's a photo of the fine actor, Nick White, who is on tap to play the lead role in "Crier."
That picture was taken from a scene from a movie called Wrightsville. It was Nick's first film role. The scene is below. You can click on the Vimeo link and watch it in high definition.