I won't bother commenting on your "all OO code is doing it wrong" rant as you and I have already been down that road many times and we will never agree and so it is not worth going down it again.

However, there is maybe some merit in my suggesting that Moose might also allow one or more compile-time switches to disable the creation/costs of the methods and data required to provide for deep introspection, for those classes that do not use it?

There is a lot of work going on to do exactly this. The idea is to basically "compile" the metaclasses and accessors once and cache them (the exact details of how that is accomplished is still up in the air). This would remove much of the Moose startup penalty and memory cost involved with metaclasses and would open the doors for other possible optimizations. I doubt though that we could replace method access with direct hash access since that involves compiling the call site and not the class itself and that can get really hairy really quickly.

As for your idea that type/range checking is only useful during development, I disagree (SHOCKING ISN'T IT!). In languages like O'Caml, the compiler does sophisticated static analysis/type inference to make sure that type usage is consistent throughout the program. Because of this O'Caml can ditch all type information at runtime, which helps to contribute to it's very fast runtime performance. Doing such a thing with a dynamic language like Perl where static code analysis is all but impossible would be a bad idea. It would be like not checking your parachute before jumping from an airplane because last time you jumped everything worked just fine.