What can we do about well-meaning editors (or editorial assistants) who cannot spell and who, in performing their duties, "correct" the spelling of a word we have already spelled correctly?  Whew!  That was a mouthful.  Let me illustrate the problem.  I do not for a minute believe Jim Butcher does not know the correct spelling of "dais," a word he uses several times in his third Harry Dresden novel, GRAVE PERIL.  However, in the paperback release of this novel the word is misspelled EVERY time as "dias."  I can only conclude that someone "corrected" his spelling of the word after he reviewed the galley proofs.  I see this kind of thing so often, I wonder that it has not already come up for discussion.  How do we writers protect ourselves from these well-meaning, but poorly educated idiots?   

BTW, both of these words pass the Word spellchecker test, so it I do not believe it is a matter of having a tool that provides the incorrect spelling to the publishing house employee.