That's like a carpenter saying it only took 10 seconds to make that cut while ignoring the 3 hours it took to create the jig so the cut would take 10 seconds.

You don't need the calculator to do the final sums until you've done all of the work gathering all of the data that needs to be calculated. It doesn't mean the calculator wasn't needed, just that it's only needed for one thing not every step along the way.

This wasn't the gotcha you think it was

near the end of the thinking yes.