[Milawe]

Do you mean that the only way to communication is via the say command, and if you don't know the other character's language, you simply don't understand them? This would mean there's no channels for chatting, and there's no tells, I would assume. Your only form of communication is say and with a language barrier. (Please correct me if I misunderstood.)

The quick answer to your question is, "Yes, it makes sense in an RP enforced MUD."

The more detailed answer is that a lot of things can make sense in an RP enforced MUD as long as you have a good story behind it. By a good story, I don't mean that you explain anything that doesn't make sense with "It's magic!" That doesn't fly with today's gamers while you could get away with it 15 years ago.

To specifically address this game design idea, you have to also question what you want to accomplish. Are you going for realism? If so, you have to decide if that's the audience you're hoping to attract. Games are usually an accelerated microcosm that mimic real life, but if they were actually like real life, none of us would play. ("I know a game called Real Life and the graphics are freaking awesome!") Do you want to make communication difficult amongst players? Keep in mind that you're running a multiplayer (hopefully) game. If you DO want to make communication difficult, why do you wish to do so? Is it another grind with the reward being the ability to communicate between players? Grinds can be very, very beneficial to a game, but before you make a player do the grind, make sure it's worth it to them or that there's a very specific game design concept behind it.

Your system sounds cool to implement, and I'm sure that it'll be fun to code. Sometimes, though, you have to take off the coding glasses and look at the whole thing with a gaming perspective. Ask yourself what the benefits and drawbacks of such a system are and what you're trying to accomplish within your game. If it fits and will promote your overall design concept, I would say implement it. If you find that the cons will actually hinder what you hope to achieve, go back to the drawing board. You could still keep the cool code and just implement a basic "common language" system on top of your random letters system.

Again, I'm assuming that you are not allowing any communications besides the say command, and learning other characters' languages is vital to the system.