I'd keep it as is. No need to introduce an extra scope. And why add the default argument for print, but not for -d?

Folks, what do you think, what is the most correct style of perl code?

Are you sure you're posting in the correct forum? Perhaps you're looking for the Python one. Perl embraces the "there's more than one way of doing things". It's the Python philosophy of there being only one right way of doing things.