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Precession and torque are uniquely important to understand in tailwheel aircraft where you are pitching the plane up and down while the wheels remain on the ground. The thing that always bothers me about the explanations personally is how rarely it is explained that precession is a function of the change in angle, torque the change in power, slipstream absolute torque, and p-factor absolute angle.

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While theoretically true, the numbers do not lie. The angular momentum of the prop alone and the applicable geometric (dis)advantage are just not enough to significantly affect a typical taildragger. Not to mention that while (both) mains are on the ground, torque has almost no effect at all (aside from the microscopic compression of the tires :)). Once you start flying something like the T-6 things change, of course, because of the large radial engine.

The effect of the P-factor (pitch asymmetry) is so miniscule that aside from making pretty pictures and explanations with a prop mock up and its shadow it can be disregarded entirely. Again, things are different in helicopters (this is why a typical helicopter tends to roll appreciably on takeoff).

I like the way this 2-minute video illustrates the increase in P factor during a climb.

https://www.youtube.com/watch?v=VJOYERf6380

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