I just finished teaching a class of about 50 maintenance people some of the nuances of water heater repair, and in the process, I learned something about my source of strength.

We were playing with some dead water heaters that had been captured on their way to the dump. I like using old heaters as a teaching tool; they have stories to tell about their lives, if you know how to look. In that looking, we were removing pipe nipples from the tops of the heaters — and some were rather stuck.

A few students said: “This is too hard. I can’t do heater maintenance.” I don’t like the word “can’t,” so I jumped in to see if this old white-haired guy could make the stubborn pipe nipple move. I put my trusty Hoe wrench from 1922 on the nipple and focused. The pipe came loose. Students were surprised.

It happened again — twice. A student was unable to budge the pipe nipple (even using my wrench), and I waltzed in and made it spin. The young guys with visible muscles rippling in their arms had no success while the old guy did — what gives?

Finally, someone asked me how I did it. I had to think for a bit, but I remembered back about 40 years when I was shown this trick: Rest your hand on a friend’s shoulder. Have your friend put both hands on the inside of your elbow and try to bend your arm down. Resist by thinking about your arm and give it all the strength it has to stay straight.

In my case, my arm bent despite my best effort.

Now, put your hand on your friend’s shoulder again, but this time concentrate on the area just under your breast bone as your source of strength and keep your arm straight. Let your friend try to bend your arm and see what happens. In my case, they couldn’t do it. My arm stayed straight.

I’m just a plumber, and I don’t know how this works, but I know it does. It turns out I’d worked this approach into my practice for decades without thinking about it. It’s simply that I refuse to walk away from a job without finishing it, and this “trick” has allowed me to finish every job.

The guys who couldn’t make the pipes come loose thought I’d bested them, but really, the point was that I’d demonstrated a tool we all have that most of us don’t use. It certainly sounds strange, but with no doubt, it works.

There are a couple of other not-so-obvious tricks I’ve learned over the years. For example, the plumber who appears to move the slowest often gets the work done the fastest.

When you go to a job, sit down and map out the work in your head before picking up a tool. Understand every step of what you’ll be doing before you start. This way, when you get going on it, things will go together smoothly and you won’t need to re-work anything. When you finish, it will be just as you envisioned. That feels pretty good.

Here’s another trick that helps me work effectively. I’ve noticed that I think in pictures. When I can get a clear picture in my mind of what I’m trying to accomplish, it inevitably works. When I can only get a fuzzy image in my head, it doesn’t work and I wind up needing to figure out a different way. So, when you have the opportunity, see if getting a clear picture before you start works for you on your next project. It just might save you some time and frustration.

The moral of my story? Sometimes it’s the subtle shifts in focus that make your actions powerful.