Well, actually, if there are floodgates to be opened, the Flashfic comm controversy would probably have done it, already. Will others write unauthorized homages or play in other people's unis without permission because of the Flashfic discussions, or because Helen wrote this story? Possibly. Is that a terrible thing? Not necessarily. Case by case, some may be unhappy about it and some may be flattered, as Xanthe was. That's true of public crit, too--some are pleased by the attention and some are mortified. Doesn't mean it won't happen, or shouldn't happen, or isn't already happening. Whether people see it as legitimate or not is an individual call. The 'rules' of fandom are fluid and change constantly, when they're recognized at all. If you want to be the voice of "hands off", be prepared for people to not agree with you, especially when you're moving in fannish circles where public analysis of stories is already happening. That attitude of openness may extend to homages and borrowing, as well.