Fellow GeekPlanet writer Pete MacKenzie has an interesting article on canon up this week, and I thought the issue of "retconning" was worth discussing.
Like Pete, I need to have retroactive continuity explained. The "shit happens" approach espoused by his other half is one I find deeply unsatisfying, partially because I have trouble with the idea that mistakes are ignorable simply because they're inevitable, but mainly because I am convinced that every single human being across the world with access to fiction has a story they regard so highly, and love so fervently, that attempts to continue that story without checking the two slot together would lead to serious problems. This, indeed, is one of the many very good reasons people are often leery (to say the least) about sequels to their most beloved works of fiction.
To me, whilst such mistakes are inevitable, they are generally speaking a sign of a someone screwing up, and should be judged as such. Screen-writing slip-ups are no less fair game than wobbly sets, hammy acting, or gratuitous nudity. Some mistakes bother some people more than others. It might not necessarily be fair to blame the writer themselves, checking the entirety of a TV show's run is probably a bit much to demand of someone writing their first episode during the seventh season, but someone certainly dropped the ball somewhere.
This isn't the whole story, of course. Sometimes mistakes are deliberately made following the conscious decision that it will improve the story. Clarke did this with each sequel to 2001, believing it more important that the stories kept up with the times than that they stayed true to each other. On a much smaller scale, Joss Whedon admits in a BtVS DVD commentary that he deliberately removing all the dead bodies for the final shot in the Bronze in "The Harvest" because it somewhat ruined the elation over Buffy's triumph to have her wading through the corpses of those she was too late to save because her mother had grounded her.
Obviously, mileages may vary. I don't like Clarke's approach but I'm fine with Whedons (not doubt in large part because Whedon had to point it out before I noticed). In truth, however, I'm not sure either of these examples gets us to the heart of why I generally dislike retconning.
It's here that I diverge from Pete's viewpoint (though we meet back up again at the end; I've been complaining about airbrushing out historical bigotry ever since the whole Vic Fontaine debacle on DS9). I freely acknowledge that retcons can work very well, and further that they can be necessary tools to smooth over mistakes and rough edges, or to simply erase spectacular creative mis-steps that have otherwise irrepairably damaged your fictional world. Sometimes you really do need to reach for the Etch-a-Sketch and start shaking, and sometimes the "it was only a dream" ending can be forgiven because you're so desperate for an ending of any kind.
Despite recognising all that - and here's why Clarke and Whedon aren't great examples - my problem with retconning is that frequently it amounts to one writer deciding that their ideas are so good they justify tampering with another writers' work.
Obviously, they might be right. There are many examples of backstory tweaking that improves the situation. Of course, there are far more that make things worse. The worst kinds of sequels aren't those that simply suck, it's those that actively damage what came before. Alien3 springs immediately to mind. Not only is it a difficult film to love on its own merits (though it is certainly not entirely without merit) the deaths of Hicks and (especially) Newt at the start of the film makes the conclusion of Aliens far less satisfying. I realise that in this particular case it wasn't a creative decision to do away with Hicks and Newt, I believe Carrie Henn and Michael Biehn just didn't want to come back. Having said that, how hard would it have been to have Ripley's pod jettisoned (possibly alongside Bishop's) but leave the other two safely on board?
Even when an author fiddles with their own work, it can bug me, since generally speaking its their fans love for what has gone before that keeps them in the money they need to keep writing, but it's far worse when the latest head honcho decides to start cutting and pasting their ideas over those of others. It is, quite simply, rude. And I don't think that's changed by the fact that from time to time, a little rudeness is called for.