Posted: 22/01/2015 at 18:20
Thanks all for the warm welcome, and especially to TinkerBEL for sending me the (very comprehensive) Paris Marathon Field Guide! It answers a lot of my questions, although I'm sure I'll have plenty more, as a rather inexperienced runner.
As such, I don't have much wisdom to contribute. I did actually live in Paris for a little while, so if anyone has generic questions about Paris, I may be able to help.
For example, the marathon guide says "We have no idea why it’s called a Convocation". I don't know if I can give a good answer, but "convocation" is a common French word for a document such as this -- an invitation, notice, summons, etc. (For example, when I applied for a job, they sent me a "convocation" that invited me to an interview at a particular date and time.) So either they decided to simply use the French term in the English instructions, to avoid confusion about which document to bring, or they found the word "convocation" in an English dictionary and decided it was a sufficient translation for the same French term.
When I lived there, there were also a few more common scams besides the "found ring" scam described in the guide, although it shouldn't be too hard to avoid them with a little common sense.