Once you invite it into your code, forget everything else you know about writing Perl. ....

I call bogus.

File and directory access is generally insignificant. If you're writing high-performance programs that simply can't wait for the filesystem, POE and IO-AIO get along nicely.

As we've seen elsewhere in the thread, POE-Component-Generic can wrap an asynchronous interface around all those blocking modules you know and love, assuming there isn't a POE::Component to your liking and you're not sufficiently motivated to write one.

Oh, right, and some POE components aren't maintained as well as they might be. Welcome to CPAN.

Because once you go the 'build our own cooperative scheduler' route, everything--and that means everything--in your program has to be be broken up into small bite-sized chunks, and retain state across those chunks, so that the non-preemptive scheduler doesn't get locked out.

Semi-accurate but exaggerated.

It really depends on the program in question. It's generally accepted that well-written code is already decomposed into bite-sized pieces: small functions and methods that do one thing well, and larger ones that are composed of glue logic between calls to the smaller ones. In this case, you may find that a lot of your code will work as-is.

POE provides ways to maintain state between cooperative callbacks, but the POE-agnostic parts of a program don't even need that.

A program that requires major restructuring to work in a cooperative environment may already have bigger problems.

It like using Lego. So long as everything you want to build has straight sides and is either a multiple of some fixed sized unit, or there is a (usually expensive) off-the-shelf part to suit, it's great. But if you want curved sides; or cirular holes; or 120° angles; or anything else that is vaguely custom--you're stuffed.

Completely bogus.

Lego are proprietary hardware. Most users can't fabricate their own bricks. POE is a suite of free, open-source software libraries, with internal and external extension APIs. If you can't find just the right component, you're encouraged to write it and share it with the rest of the world.