In that case, would it follow that the output strings could or should be declared as named variables?

Because it's good practice to name constants like this. It gives them "meaning" and makes them easier to find.

Generally, the more things you give an explicit name, the easier your code is to comprehend.

Efficiency is barely affected but yes, that's clearly over-engineered.

you're kidding...? that's a description that could be considered too long x) (but it's not).

=> not an issue in any way, closing.

Fixed.

Where does the syntax " => " come from? What does it do?

Good point! I updated the 2nd paragraph to add this.

Correct.