I feel the imperative here is to create a simple pattern that can allow non-gpl IP to run as a plugin of a GPL framework legally and outside of the GPL. The following quote directly from the GPL (bold added for emphasis) proves my pattern:
Below is a simple application of this pattern as a Joomla component:If identifiable sections of that work are not derived from the Program, and can be reasonably considered independent and separate works in themselves, then this License, and its terms, do not apply to those sections when you distribute them as separate works.
File: "widget.php" contained in "mysite.com/components/com_widget" and invoked within Joomla with the following URL: http://www.mysite.com/index.php?option=com_widget
//from this point forward are identifiable sections of this work that are not from Joomla! IP
$name = 'FreedomFighter';
As you can see from the above, identifiable sections of that work are not derived from Joomla!, and can be reasonably considered independent and separate works in themselves due to the fact that the program will run without Joomla! and when this IP is distrubuted as separate works the only logical outcome is that the GPL License, and its terms, do not apply.
This is the most simple way that I can describe this pattern. I understand that the component is extremely simple, but it proves beyond doubt that there is an opening and a legal one at that. Using the above pattern one can quickly implement the tools needed to provide the rest of the functionality and soon be deploying non-gpl licensed extensions for Joomla!