Sounds like a damn good teacher to me.
What it shows me is the teacher wants more than regurgitation, they want understanding of the principles they teach.
You are handed a tool bag with hundreds of tools. While you could grab a sledge hammer to solve every problem there is usually a more effective way to stop a leaking faucet. Understand your tools and what purpose they hold, then you will also learn in a pinch a wrench can also be a hammer.
While the Pythagorean theorem won't fix a flat tire I know If I have a piece of wood and a spare and my jack doesn't work I can still get my tire off the ground to change it.
Don't under value teachers who teach the essence of problem solving. One day you might be stranded on a desert highway and have to engineer a solution to a problem you never got on a study guide.