There are a variety of editorial truisms: long sentences are hard to read; lists should be parallel; consistency is good. This wisdom is taught, and it's reinforced by personal experience; editors are themselves readers, after all, and they monitor their own reactions when reading.
However, there isn't always hard data that editors can point to to support what experience and insight tells them is true. But sometimes there is, and just this week I ran across something that underscores the editorial push toward consistency, and I was pretty excited about it.
I'm in a linguistics class right now, and one of our lectures was by the linguist Gareth Carrol, who uses eye-tracking studies to understand how people read. He started his lecture by noting that people do not read smoothly across the page, line by line. They stop on words (fixations); they jump (saccades); they back up (regressions). By studying what's happening with these movements, linguists can determine where people are having trouble with a text, and importantly, where they're not.
Heat map from eye-tracking study (source
In our lecture, he discussed binomials, which are pairs of words linked by and: fish and chips, bread and butter, salt and pepper. An interesting thing about binomials is that they have a conventional order: people say I'm sick and tired of it; they don't say I'm tired and sick of it.
Eye tracking studies have determined that people can read binomials quickly. It's like the brain sees a familiar binomial and says "Oh, I get this" and can flit to the next bit of text. In an experiment, Carrol and his researchers wrote some stories that included invented binomials—pairs like wire and pipes and leaves and grass. These are perfectly normal pairs of words, but not binomials that have a conventional order.
So what did they learn? A couple of things:
- People took longer to process these unfamiliar (invented) binomials than to process familiar ones. But …
- If people saw the same invented binomial four or five times in a story, they acclimated to it and were able to process it faster.
To my mind, this translates easily to the editorial guideline of consistency.
Of course, I'm in the world of tech writing. We already know in our world that readers don't really want to read-read; they want information, and the faster, the better. If you want to reduce friction for the reader (that is, reduce fixations), be conventional. Use words consistently and construct text consistently. By doing this, science says that you're reducing the effort that the reader has to make to process the text, and the sooner they can back to doing whatever it is that they were reading about.