Nope, having a fake #! line will cause a fatal error, even if you invoke perl explicitly: perl poem.pl because Perl detects the #! line and tries to exec the specified command, just like a shell would do: Can't exec Ambiguity! at poem.pl line 1. This is documented in perlrun:

       If the #! line does not contain the word "perl", the
       program named after the #! is executed instead of the Perl
       interpreter.  This is slightly bizarre, but it helps
       people on machines that don't do #!, because they can tell
       a program that their SHELL is /usr/bin/perl, and Perl will
       then dispatch the program to the correct interpreter for
       them.
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