You know the feeling. Four ideas are juggling in your brain and you need to get them down on paper. They shift around as you struggle for the best order, put in transitions, and write your paragraphs. After all, you want your reader to experience the material just as you did and this is hard. But at last you are done. Your ideas are pinned down and your brain can relax. You stretch, look at your empty coffee cup and prepare to get up.
Don’t! This stopping place exactly the worst time to take a break. Instead, keep going. See what comes next and write down a couple of sentences, some thoughts, or even just a few notes. After all, you know what will come next since you were just now so enmeshed in what came before. It can be the work of a few moments to get these thoughts down.
Then, when you return to work after your break, you will be able to dig right in without recalibrating. You will see where you are, in the middle of something. The activation energy is not nearly so great as it would be if you had actually stopped at a break in the material.
Another danger of stopping at a stopping place is that you might pick up something else instead of continuing work on this project. You might have teaching to prepare, or take the time for a review or a letter of recommendation. These are worthy tasks, but they should be left for their own time, perhaps late in the day when your own writing on your project is done.
The wisdom of never stopping at a stopping place applies to all projects, big and small. As long as the project is not complete, work a bit into the next section before you stop. Writing a book? Towards the end of it when you might be more involved with editing and publicizing, write a few pages on your next book. Writing the discussion of a paper? Begin the next section before a break.
Whatever you do, make sure that beginning to work again is as easy as possible and that happens when you are still in the middle of an idea, not at its end.