to not have a characters' words typed out phonetically, when they are saying things that sound different from how they are spelled/correctly pronounced? A black character might say "thing" and pronounce it, "thang" for instance. I would feel uncomfortable writing it this way. Would it feel forced to explain that the character said it with an accent?
Phoneticize dialogue at your own risk. You may be able to get by with some, but if you overdo it, you will quickly annoy the reader. You should mostly use word choice (dialect) rather than phonetics (accent) to convey localized speech patterns. Some phoneticized words, like "thang", are common enough that they aren't much of a speed bump to the reader. But if the reader has to stop and sound it out instead of recognizing the word holistically, you'll murder your dialogue.
Phoneticising written language was popular among African American writers as a way of emphasising difference - it reflected how they spoke, as opposed to 'Imperial' English. With those writers, it was an act of protest and an assertion of cultural identity...unless it contributes something valid to your work I'd avoid it.
For me, phoneticised writing accentuates dialog. More than that; it shoves the character's manner of speech in my face, far more aggressively than through other means (such as choice of words, sentence structure, and so forth). If you really want the character's manner of speech to influence my perception of it, use it. However, if all your characters use dialog of this sort I'll just get confused and distracted. I prefer not to use it at all.
