Well, the problem with speaking "arcane" is that the arcane words are really spell components.
To say it another way, "Words have power."
There are three basic kinds of spell components: Verbal, Somatic and Material. Verbal are the spoken words and sounds during casting, somatic are the gestures, and material are the bits of goo and such that mages carry around in smelly pouches. Every arcane spell uses one or more of these comonent types. Anyway, a simple conversation in "arcane" would probably result in funny discharges of energy at unsuspecting passers-by, as some spells have only verbal components....especially if someone has taken Still Spell *grins*.
Now that I think of it, this might be fun to code such that using this ear would result in random discharges of magic...hehe
Anyway, the point is that such a language would not be conversational at all, but rather a required tool of wizardry.
