Not a Very Faithful Transliteration
Commonly, the YIVO (nearly every other) system for transliterating Yiddish into Latin characters operates according to spelling, rather than pronunciation; thus האָבן remains ‘hobn’, even when pronounced ‘hobm’, and קױף becomes ‘koyf’ whether the speaker in question happens to say ‘koyf’ or ‘keyf’.
But it occured to me that of course it’s not strictly a literal transaction—or if it is, that it’s a lossy one. Because even as simple, regular and phonemic as Yiddish spelling is, 99% of the time, all bets are off when it comes to words of loshn-koydesh (Hebrew or Aramaic) origin. Not only do we not transliterate that phrase, <lshun kudsh> (understandably), we also don’t differentiate among homophonous letters that crop up in those words. In words that obey the standard spelling rules, Yiddish is pretty good using only one letter for any given sound. But when you introduce loshn-koydesh words for comparison, you start seeing redundancies: ק and כּ, or כ and ח.
And of course, we don’t differentiate among them in transliteration. They both become k and k, or kh and kh, respectively. But I wonder if we would find it more useful if we spelled things— well, it’s hard to think of what letter you’d use. ק, for instance, is often transliterated as <q> from Hebrew, but of course it’s become the dominant k/q letter in Yiddish so unless we want to start saying qoyfn and qoydesh (and I’m not saying I would be against it; Qs are fun), there’d be some figuring to do.