I've touched on this in comments posted about the wiki, but I feel like it needs to be explained properly in one place.
I think the spelling mistakes (and more importantly, the patterns of spelling mistakes) in My Immortal mean it was for real, not a troll fic.
I say that because I've tried writing deliberately so-bad-it's-good fic in the past. (Not a genuine troll fic, since I admitted it was a parody from the start, but the principle is the same. Close enough, anyway.) I soon worked out that there are four - yes, count 'em, four - different types of bad spelling:
- Deliberate Molesworth-style "Down Wiv Skool" spelling to show the world how rebellious you are. Because this is done for effect, you need to make sure everyone can still read your story. The mistakes can't be too big, and the words still make sense if you read them phonetically.
In Tara's case, these are words such as "da", "deze", "goffik", "blak", etc. as well as textspeak like "ur" and "ppl", and rude versions of tearcher's names like "Sodomize" and "Slutborn". - Words that you genuinely don't know (or just can never remember) how to spell, but you're having a good try anyway. Again, these are all easily understood if we read them phonetically.
At first glance, Tara doesn't seem to make many of these mistakes. "Loopin" is probably the most obvious one, and possibly "whizard", as well as many missing apostrophes. - Genuine typos, where you accidentally hit the wrong key, or miss out a letter, add a letter, or transpose two letters. (This is the type of mistake I make most often.) We're more likely to make these on words we know well, because we take more care typing unusual or unfamiliar words.
Tara;s typing is even worse than mine! She makes too many of these to list here, especially when Raven isn't around to check. For example, "ressuredly", "teardully" and "argreed". - Autocorrect can make any of the above mistakes worse by "correcting" them into the wrong word. (It also does it to good words that aren't in its dictionary.) Depending on how much the word has changed, it can be very, very surreal. (I once heard of an attempt to spell "bronchitis" that ended up as "brown kites.")
Tara's writing normally does this when Raven is editing. The results include things like "his womb", "Azerbaijan", "Sinatra" and (possibly) "Bombodil".
So what does this have to do with trolling? Well, people say things like, "Tara must be a troll, because it's stupid to believe she can't spell 'eyes' but spells 'Azerbaijan' perfectly."
But trolls are making deliberate mistakes, so they want you to understand what they've written so you can appreciate how bad it is. That means lots of the first type of mistake, and fake versions of the second, but fewer of the last two. (e.g. Some trolls will correct genuinely bad typos to more-legible-but-still-wrong ones.)
A typical troll would write, "Snap grabed the kamera," or "Snape grabbd teh cammera," not "Snoop garbed the caramel." They need to be understood.
Even the best trollfic writers don't manage to come as close to matching Tara's style. In Moon Daughter, XxMoonlitexx tries to recreate the Tara/Raven feud with her imaginary betas, but the pattern of spelling mistakes remains the same whether the chapter supposedly had a beta or not.
That's why I think My Immortal is not a trollfic.