Well, I didn't know where the question would lead exactly, but I think your post has the real key, and that is:

To test a procedural script w/o affecting regular run-time behavior, 'require' the script into your test script so you have access to it's subroutines.

Thanks to you and everyone, the PerlMonks never cease to impress me. With this kind of support, no wonder 4 out of 5 dentists who code prefer Perl!