First, I think that anything that adds to a given feature in Perl, whether I use it or not, is a good thing. I like your ideas and would love to see the discussion go further. That said, I have a pretty good idea of why p5p might be ... reluctant to do more with lvalue subs.

I maintain a webapp that's half in Perl, half in Javascript. It's almost 8 years old and there have been at least 15 different people who've worked on it, then walked away. There are no more features for this thing - just bug fixes. And, each bugfix, no matter how trivial, takes at least a week from start to finish. I just wrote up a proposal to fix a bug that affects one aspect of one feature when it's used with another feature. This fix will take at least 3 months and involve testing the entire application. Reason - the bug is in a function that every feature in the application uses.

Perl is kinda like that. It's not a clean, well-factored application. The guts are a mess of C macros, typedefs, crazy optimizations, and OS-specific code. When you start messing with something as integral as subroutines, you never have enough regression tests. You're talking about affecting a core subsystem that, probably, many other subsystems depend on in some way or another. And, it may not be clear what depends on it. I've fixed bugs in section A that exposed hidden dependencies in section G.

However, despite all that, I think the discussion is definitely a good one. Without a lance, you cannot tilt at windmills.