My first "Light bulb moment" was the second day of my first long tour when I realized I should have asked experienced riders for advice. (I rode with blue jeans rather than padded riding shorts and ended up with severe heat rash so painful I could hardly walk)
My second "Light bulb" moment was the second day of my second long tour when I realized I should have asked for DETAILED advice from experienced riders. (I rode with the padded shorts, but wore cotton underwear, and still received nasty "bum rash")
Now, even after many long tours, and being comfortable with my equipment, and knowing what to expect, as well as how to pace my body, I am always asking questions and reading this site to glean any new info which I might use.....the "extra wheel" is a good example.