Second, there isn't much difference in effort to write the three line boiler plate:

    #!/usr/bin/perl
    use strict;
    use warnings;
[download]

    #!/usr/bin/perl
    use Modern::Perl;   # Or whatever todays fad boilerplate is
[download]

Now one may argue "but my 'use Shiny::Boilerplate;' includes a whole shit load of additional modules", but that only makes your boilerplate less generic. Because for each additional module/pragma in your boilerplate, a significant (probably > 50%) part of my programs/modules doesn't need it.

Second, there isn't much difference in effort to write the three line boiler plate:

It's not effort to write; it's effort to explain and to understand.

If you want to write your own book where you tell novices "Include these three to seven magic lines at the start of every program you write, but don't worry if you don't understand them, they're really important, trust me, and yes I meant every program you write!" be my guest. My goal was teaching Perl novices to write code somewhat better than they could with Perl 4 (and not to clutter every piece of code where I happened to use say or given/when or state with use 5.010; or use 5.012;).

If you want to write your own book where you tell novices "Include these three to seven magic lines at the start of every program you write, but don't worry if you don't understand them, they're really important, trust me, and yes I meant every program you write!"

You must misunderstand me.

If I say my boilerplate is:

#!/usr/bin/perl
use strict;
use warnings;
[download]

I don't intend to write that as:

#!/usr/bin/perl
use
strict
;
use
warnings
;
[download]

Three lines is just 3 lines. Not 7.

As for explaining, I rather explain the benefits of "use strict" and "use warnings" then "oh, just download this magical thingy from the internet, written by some dude, who will tell you just to trust him and use the magical thingy everywhere".

In my years as a trainer, I never explained things away with "oh, this is just a magical thing which I won't explain, just trust me, use it". I'm not that lousy.

What book? There is no book mentioned in the root