Why do you need an event for the formatting (stylesheet)? Why can't it just **be** the format (file type)? And then you link those PDF's, epubs, etc... to the index event.
Discussion
You already have a format type (Asciidoc). This is for display or export to other types.
You don't want to have a bunch of event-copies containing different formatting, as you'd then have to change the event content in each copy, to edit it. Nightmare.