The problem with writing dialect is that it makes reading and understanding unnecessarily difficult. We do not read the sound of a word, we read how it looks. If we encounter a word hardly ever seen before, we need to take that detour by saying the word in order to understand it. It should not be the norm, however. The same applies to punctuation as well.
Of course, if you and the people you communicate with always use a specific written representation of dialect, that point becomes mute, as you'll readily recognize the words from seeing them.