Is it, at least in rare cases, possible to guess a command word for certain COMMON magic items? Perhaps a semi-mass-produced fireball wand from one ancient empire had a pool of often reused command words to ensure that the mage-soldiers could use the wands despite any filing errors that might separate command word from item.
“After the humiliating defeat of the battle at Zanderqwell, where a clerical error (or deliberately sabotaged) documentation mixed up all the command words of a vital shipment of wands to a Zaharan mage unit, it was mandated that all such wands made in the kingdom would be assigned a standardized command word: ‘DIE IN A FIRE’ spoken in Zaharan. Other common items had their command words similarly standardized to a greater or lesser extent, some items having a handful of competing standards. This rule continued for the better part of a century, losing favor around the start of the 3rd Great Thrassian Rebellion when rebel spell-casters started to intercept shipments of magic items.”
This would probably be rare, but I could see certain incantations and command words gaining popularity in certain eras and regions. Someone who has done a great deal of study in this area (enough to get one or two proficiency levels), might know a couple good guesses.