writes:

What part of "tends to sharpen attention, and increase the heart rate" do
you not understand?

As I've explaind, if you need a risk of death to sharpen your attention,
there's something wrong. A disciplined pilot pays careful attention whether
his life is on the line or not, and he does it without tachycardia.

Very carefully, obviously.

How do you determine which is riskier: actually doing a dangerous maneuver in
order to learn how to recover from it, or learning to avoid it and/or learning
something else in its place?