Like Joost, I am a bit skeptical about the need for this "optimization." If the performance of your application hinges on the speed of accessing subroutine arguments, then I think Perl might not be the right choice. Have you done any profiling to see if this is the case, or are you simply stabbing in the dark? I suggest you do the former, rather than the latter, when it comes to expending time and effort to optimize your code.