No. Next question.

Seriously, CGI.pm is a terrible example of interface design. The OO interface is constantly breaking because of the need to support the non-OO one, which relies on lots of globals and requires crazy stunts in long-running environments like mod_perl and FastCGI.

Here are some reasons to avoid mxing:

• Inevitably means more code to maintain, test, and change. Your code would require changes in multiple places if you modify the parameters a function takes.
• Ruins OO features like inheritance.
• You didn't actually do this in your example, but having some subs that are called as functions and some that are called as class methods in the same package inevitably leads to confusion and bugs caused by mistakenly calling one the wrong way.