I am not too sure what you mean by "linguistic magic". And I have to disagree with your statement that it can't be learned by trial and error. The main reason is the the opposite of that (imo) is by rote. which to me implies repetition. Which conflicts with your next statement.
My thought as I read your post was a sort of magic where every spell is unique, and cannot be reproduced after being cast. Your power depends on your understanding of what has gone before and how to manipulate the nuances of power in different, sometimes very subtly different, ways. The beginner will not be subtle, but the master will see ALL the subtleties and therefore able to harness a lot more power, but is he completely sure that the spell he is casting now HASN'T been cast before?
Now, all that may be nice, but how you would put that into a game system I have no idea. Just where do you plan on using this system? Novel? RPG? Computer game? You will have to tailor it to where you use it.