One pair of katanas in the game?

[HakuroDK]

Then you remember, using lore, that they never explained why Arcanist went from Trap users that used Mechanical staves and automatons to suddenly becoming summoners, as well as why we suddenly have daggers being sold everywhere when they weren't before. A lot of items we have access to aren't native to eorzea either, but yet here they are.

Were mechanical staves ever part of the lore? I seem to remember the Arcanist's Guild being just a bunch of harbormasters. The mechanical staves were in the concept art at one point, but never in the lore did they ever wield them.

Also, daggers were sold everywhere before, but they fell out of favor with the Gladiators and became unpopular, thus stopped being sold for a while. Then when the Rogues started accepting applications, daggers became popular again.