Repetition in narrative is a tough problem to crack because we are used to the way our narratives flows. Recaps of action that happened previously in the book make us feel more confident that our writing isn't confusing our readers. And surely confusing our readers should be avoided at all costs? What have we got to lose when we remind readers of the context?
Don't remind me!
If you are strict about cutting repetition in narrative, your plot will flow more smoothly and your readers will be caught up in anticipation of the next thing. When we remind readers of the context, we condescend the readers who are caught up anyway and take away the suspense from the readers for whom it had not yet clicked. Whether they got it or not, our little reminder has ruined their experience.
Finally! A use for those notebooks
When reading through your draft, keep a notebook next to you. Make brief notes about each chapter and scene using a key. The key needs two identifiers.
An event or detail.
An event or detail being recapped.
Use two colours or two different types of bullet point. Whatever works for your brain.
When you come to a recapped detail, think about what effect this will have on the reader. Do they really need to referenced again? Or can we trust our readers to connect the dots?
Repeat, repeat, repeat. Cut, cut, cut.
Recapped information can crop up in two ways. 1) it happens in a scene and is then referenced later on in exposition. 2) it happens, and then character dialogue mentions that it happens. The former may take several chapters to be recapped, the latter could appear immediately.
Relating back to relevant information from a previous chapter may seem like a good way to refocus your readers on the context, especially if it is relevant to something that's about to happen. However, it can feel to the reader like the narrator or one of the characters is looking them square in the face and saying "Hey, do you remember that thing we told you earlier? Well, listen up because it's relevant now." In many cases, it is more impactful to plough on through the narrative and leave your readers to think "Oh! That's why I was told that!"
The other type of recap to watch out for is in dialogue. It is this type that disrupts the flow of the scenes and can diminish the impact of the action.
He threw the book at his friend. "Ouch, why did you throw that book at me?"
Here, the dialogue repeats the action. If this crops up in your work, consider the effect of removing the narration in the context of the scene. A character out-of-the-blue saying "Ouch, why did you throw that book at me?" might not make sense. But if your scene has established one character holding the book and bickering with the other character, dialogue without the preceding action being described could be the immersive way to go.
Trust your readers
When you cut out unnecessary recaps, your readers experience an immersive novel that challenges them to connect the dots on their own and allows them to experience related events from your character's perspective.
If you want an example of this done both right and wrong, go and watch Arrested Development. Seasons 1-3 are told in a non-linear fashion with narrated exposition that occasional refocuses the reader. Viewers feel clever when they get something and like the show is clever when they didn't get it until the reveal. The reboot spends about 50% of each episode recapping past events. Viewers are sat thinking "Yes. I know this. Get to the point."