Designing Effective Technical Training

We have all sat through it. The most brilliant person on the team stands up to teach the rest of us something they know cold, and forty minutes later half the room is quietly lost. The slides were dense, the pace was brutal, and somewhere around minute ten a term went by undefined and never came back. Afterward the expert is baffled. “I explained everything,” they say. And they did. That is exactly the problem.

Being an expert is not the same as being able to teach. These are separate skills, and assuming one implies the other is how good organizations end up with terrible internal training.

Why knowing too much gets in the way

The villain here has a name: the curse of knowledge. Once you have deeply learned something, you cannot easily reconstruct what it felt like not to know it. Your knowledge has become automatic. A senior engineer looks at a command like git rebase -i HEAD~3 and sees a single, fluent gesture. A beginner sees a string of unfamiliar symbols, each one demanding attention.

That difference is not about intelligence. It is about how memory works. Working memory - the mental space where we hold and manipulate new information - is famously small and short-lived. Experts have spent years compiling thousands of facts into compact mental chunks, so a topic that floods a beginner’s working memory barely registers in theirs. The expert genuinely cannot feel the load the learner is carrying. Researchers call this the expert blind spot.

It produces the same three mistakes, over and over:

• Skipping steps that feel obvious but are invisible to the learner.
• Using jargon as if it were plain language.
• Going too fast, because the material is not taxing the teacher at all.

None of these come from arrogance. They come from competence. That is what makes them so hard to notice and so common.

Explaining is not teaching

Here is the deeper trap. The expert’s instinct is that teaching means explaining: transfer what is in my head into yours, clearly and completely. But learning does not work by transfer. People do not absorb understanding by listening to a clear account of it. They build understanding by doing things with the material - retrieving it, applying it, getting it wrong, and trying again.

This is why the polished lecture so often fails while a messier, more interactive session succeeds. Decades of research point the same way. Re-reading and re-hearing feel like learning because they feel easy, but that fluency is an illusion. The effortful work of pulling an answer out of your own memory is what actually builds durable knowledge - the so-called testing effect. The popular book “Make It Stick” lays this out for a general audience, and the punchline is uncomfortable for anyone who loves to lecture: if your learners are only listening, they are mostly forgetting.

The good news: teaching is learnable

If expertise does not grant teaching ability, what does? A handful of habits, none of which require a degree in education.

Start with outcomes, not content. Before building a single slide, write down three or four things a learner will be able to do by the end, using verbs you can actually observe - configure, debug, build - not “understand.” Those objectives become the filter for everything else.

Respect the limits of working memory. Teach one idea at a time. Define every term the first time it appears. Cut anything on a slide that is not doing real work. Assume nothing is obvious, because to your learners, it isn’t.

Make people do the thing. For every chunk you explain, give learners something to retrieve or attempt. Show a complete worked example first, then gradually remove the support until they can do it alone. Aim for tasks that are hard enough to require thought but achievable with effort - the zone where learning actually happens.

Check understanding constantly, and not by asking “does that make sense?” People nod regardless. Have them do a small version of the task. Use a quick question with think time. Notice where they get stuck, because that tells you where your explanation was thin.

A more honest standard

The shift that turns an expert into a teacher is mostly one of attention. Stop measuring the session by how much you covered and start measuring it by what learners can do afterward. That single change forces every other good habit: it makes you cut content, slow down, add practice, and check results.

So if the best engineer’s workshop flopped, do not conclude they are a bad teacher and give up. Conclude that teaching is a skill they have not yet practiced - and one worth practicing, because the same rigor they bring to systems works beautifully on lessons. Expertise got them the knowledge. A little instructional design is what lets them give it away.