Maintaining a separate twisty contrib next to TwistyPlugin is laborious. I doubt anyone will use it outside of TwistyPlugin.
In fact, the only contrib that is importing one of the contrib files is QuickMenuSkin, and it doesn't need to as it is using the plugin code as well.
Description and Documentation
My proposal is to put the css and js files in the plugin package and deprecate the contrib.
-- Contributors:ArthurClemens - 22 Jun 2007