in reply to
Perl 5 Optimizing Compiler
You've probably seen PDL, but their approach is to provide XS/C based Perlish interfaces that lighten the overhead of things like Perl data structures and provide access to more exotic processing environments like GPUs and threading.
I am suggesting this because what you're asking about is something that bubbles up occasionally, and it almost never ends well. In otherwords, the idea is to some how optimize the language/interpreter and creating a "real" compiler (err...Perl to "harnessed C" transformation tool), but what ends up happening is that compromises are made and things are offloaded to modules via XS.