Yeah, I definitely agree that you have an angle that's been very little explored. What I was thinking was more that it might give you some analytical leverage to be able to compare similar groups of fans with similar cultural practices (social networking, fic writing), who differed in terms of whether they were interacting with real or fictional characters. Something to offer a nod to in an opening chapter, perhaps.

Strikes me also that there might be a difference between fandoms where you could actually track the impact of the death event, and fandoms where you couldn't. King Arthur's death, for example, is a key part of the Arthurian legend but it's been part of the legend, I'd assume, as far back as we can trace. (Then you get into the question of whether he actually was originally a real person, but that's a whole other can of worms.)