Let me try and be more accurate and understandable.

There's a difference between "slow and horrible" and incorrect. You're not doing anything incorrectly! :)
The set up you have with Plack::Handler::Apache2 is correct but not optimal and has its disadvantages. If you can do it differently (such as having persistency) it will be more worthwhile.

The deployment document was mostly written by the community and contains practical information about situations people encountered, sometimes without any ability to change it. Our most recommended set up is Varnish <-> Nginx <-> Starman <-> Dancer. However, sometimes you're using Apache, sometimes you don't have a reverse proxy, sometimes you don't have caching up front, sometimes you can't run a Perl webserver (like Starman). These are all limitations you might face, and the deployment procedure tries to help you with that.