If you're a KJV-onlyist, if someone asks for an explanation on a verse, do you respond in a KJV-like fashion?
If someone says "What does Psalm 42:1 mean, 'As the heart panteth after the water brooks, so panteth my soul after thee, O God.'" Do you say, "It meaneth that thou heart dost desire God asmuchso as a deer desireth water on a hot day." I'm not trying to poke fun at that type of language (though I think I did make up some words in the process...), but honestly, if that's the only "true" translation then shouldn't all "true" Christians be speaking in that way?
I imagine you would explain it by saying "It means that our soul longs for God much like a thirsty deer pants for water." You're translating it into a language that is understandable, which is what other translations do. Like Tintin said, language evolves, but the message behind it does not.