Insight

Stop Practising the Part You Already Know

Grace·Thursday, October 29, 2026 Edition

THE COMFORT OF GETTING IT RIGHT

"I kept doing the chapters I was good at," said Fen Okafor, closing a textbook she'd been studying for three months, "and somehow the exam still surprised me." She said it quietly, as if confessing something embarrassing. She was sitting across from her study partner in a library whose radiators knocked all through the cold months. The exam was two days behind her. She had passed, barely.

Here is what happened to Fen, and what happens to most of us. Blocked practice — drilling one type of problem until it runs smooth — feels productive because fluency is easy to mistake for mastery. But fluency is not learning. It is what learning looks like when it has stopped. The moment you move to unfamiliar territory, the skill dissolves. Interleaved practice, mixing problem types within a single session, slows you down and makes you feel stupid. That feeling is the sensation of your brain actually building something.

Fluency is not learning. It is what learning looks like when it has stopped.

The clearest case for this comes from research on mathematics instruction. Studies comparing blocked and interleaved practice, including work published by Doug Rohrer and colleagues in the 2010s, consistently found that students who mixed problem types during practice outperformed blocked-practice peers on delayed tests, even when their initial performance looked worse. The gains weren't small. The students who felt they were struggling more were the ones who learned more.

WHERE YOU ARE STANDING RIGHT NOW

So you are standing at your desk, or the kitchen table, or in front of a screen, and you have forty minutes to practise whatever it is you are trying to get better at. A language, a instrument, a technical skill. The easy version of the next forty minutes is clear: do the thing you can already half-do and feel the satisfaction of it getting smoother. The harder version is to stop mid-flow and pull in something adjacent and unresolved, something that makes you slow down and search. Both feel like practice. One of them is. Fen's forty minutes always looked like the first kind.

You will not feel the difference today. The discomfort of genuine learning has no immediate reward built into it, which is why we avoid it so reliably and so cheerfully. But the smooth run through familiar material is a story you are telling yourself about how much you know.

🎯

Try This

Before your next practice session, write down two problem types you've been avoiding because they feel hard, and commit to starting with one of them — before touching anything comfortable. Set a ten-minute timer so the resistance has a container.

How?

Key Facts

*Blocked practice — repeating one skill type until it feels easy — creates an illusion of competence that evaporates when the context changes.

*Interleaving different problem types in a single session feels harder and slower, but produces learning that transfers to unfamiliar situations.

*This week, deliberately interrupt your smoothest practice routine by inserting one unrelated problem type before returning to what you were working on.