I've learned something, lately, about myself when I'm plotting. In my work-in-progress (A Spy Worth Saving: Book 4 in the Seductive Spies series), there's currently a long lull in the action, and for days I've been staring at my plot notes, not knowing where to go from here. I know where my plot must go in the long run, but I've been stuck in a short bout of writer's block. I've thought about it every day, and long into each night, without success; not a single plot point has come to mind.
Then suddenly, it happened. I abruptly became fed up with this immobility, and I started writing plot notes for a fight scene. It was like magic. The words started flowing, my pen going so fast that my notes are barely legible... And then it hit me. Every time I've ever been stuck in my writing or my plot notes, it's been an action scene that's drawn me out.
Instead of continuing with the inaction, I've maneuvered my hero and heroine into a sticky situation. Now, their personalities get to shine, giving them dialogue and action without my having to force it. The scene merely unfolds, and I no longer have to stare at my plot-less notebook and blank computer screen.
I don't know why, precisely, but I know that for me a good action scene is the cure for writer's block.