Yes this would work, even though the message could get garbled including the checksum, you make the first set of characters be a checksum for the rest. If the checksum or message became compromised it would fail validation. This is the best solution so far. Send it with every message.

Or use error-correcting codes so you can get your list accross even if you're drunk :D

That probably would've worked fine in WoW yeah. Definitely not in EQ though, the "smashed" level made it pretty much impossible to communicate (outside of the channels which were added later on), and the game became… challenging to play

What do you mean by error-correcting codes?

I think it's safe to assume that a drunk checksum would fail to match the message, drunk or sober. So check summing the checksum may not be needed.