As a medievalist, one of the trickiest things to deal with is transcription of our documents. We take specific classes in paleography, which is simply the art of deciphering centuries-old styles of handwriting.** So, first you learn Latin, then you learn the complicated system of abbreviations, symbols, ligatures, and contractions, and how to count backwards and consider the date of Easter when a document is dated something like ".xiiii. kalendis ffebrerii anno quod supra." Not to mention (though I guess I will) the fact that some letters look entirely different from the way they do now, some (such as c, t, and r) are nearly indistinguishable from each other, and a lack of dots on the "i" makes figuring out a word like "minima", written in cursive, nearly impossible to figure out. There are, of course, some guides to this, but they don't cover everything. Add to that the inevitable holes, liquid stains, ink bleed-through... well, you get it.
And then, just when you think you've got it figured out, some punk decides to start writing in the vernacular, but in some messed-up medieval version of it.
Advantage: they abbreviate less, because all the good abbreviations are in Latin.
Disadvantage: There are absolutely no orthographic rules, and while you might take a course in medieval Latin before you hit the archives, and if you're an England specialist you will have studied Middle (or Old) English, you probably won't get one in medieval variants of Venetian, or Breton, or Gallego, or Provençal. Unless you're at some super-fancy school, in which case: Thhbbbtttt!!!!
Anyway, I'm here transcribing (most emphatically not translating) and summarizing stacks of documents in the vernacular. I'm finding it's going more quickly than I had anticipated: I can get through 100 lines a day right now, rather than the 50 I had reckoned with. Of course, this may be a function of the document type -- some are just easier to work with than others. But I remember what a slow slog this was as I worked on the dissertation documents. And it's nice to know that there are some things that your brain actually hangs on to, other than Brady Bunch episodes and that Schoolhouse Rock song on the preamble to the Constitution.
**In that, I understand, we may be more fortunate than our colleagues who study the 18th century: while the handwriting they have to deal with is not as difficult, there are no specialized classes to train them in reading it. They just have to figure it out as they go.