Bible translations commonly adopt primarily one of two philosophies for determining the correct English translation of the Hebrew or Greek text. The first is “formal equivalence” or “word-for-word.” Here the translator takes each Hebrew or Greek word and attempts to translate it into the equivalent English word. An alternative approach is “dynamic equivalence” or “thought-for-thought.” In this case, the translator first attempts to determine the meaning of a complete phrase in the original language, then picks the English words that best convey the same meaning. The translators of the Holman Christian Standard Bible (and perhaps other translations) have opted to use “optimal equivalence” which might be explained as “as literal as possible, as free as necessary.”
I like the idea of “optimal equivalency.” The way I would phrase it is, “word-for-word as much as possible, unless it produces confusion.” I tried to think of an example where a word-for-word translation would create confusion, and although it’s not a great example, consider the following scenario: let’s say I’m translating the phrase “la bota negra” from Spanish to English. I look up each word in the Spanish-English dictionary, and I see that la=the, bota=boot, and negra=black. So the literal English translation would be “the boot black.” According to the American Heritage Dictionary, a boot-black is “a person who cleans and polishes shoes for a living.” However, anyone familiar with Spanish knows that the modifier (adjective) comes after the noun, whereas in English we put the modifier in front of the noun, so the correct English translation would be “the black boot.” This would be a case where a truly literal word-for-word translation would be a bad idea. Then, of course, sometimes a truly literal word-for-word translation isn’t even possible, because there is no one-to-one correspondance of the Greek or Hebrew word with an English word.
There’s also the issue that what is clear to one person might be confusing to someone else. Something that might be easily understood by an English major might be quite confusing to someone who struggled to graduate highschool. In that case, there is certainly a place for a variety of translations at different reading levels. Unfortunately, simplifying a translation can also require sacrificing some accuracy sometimes.
What if the original language is confusing? Should the translator take his best stab at the intended meaning, or leave it ambiguous so the reader can take it either way? This is a judgement call that the translator has to make, in part depending on how much confidence he has in his ability to interpret the true intent of the passage.