I don't know anything about the backstory behind this issue, but I started trying to teach myself hangul about a year ago, and I can tell you at least from a west-coast-american standpoint... It took me about 6 months to learn how to properly pronounce 어 because we don't have that vowel sound in our vocabulary at all... and the difference in sound between 에 and 애 is also really hard to distinguish. To this day, I have to use the french word "pepe" as a guideline for which is which. The first syllable is "peh" and the second is "Pae" but the sounds are so close to the same thing that there are a lot of english words where an "e" or an "ae" could be interchangeable in the way they're pronounced.
The official romanization of hangul - for that reason - isn't really that useful for english readers, I've found. I never use it. I figure, just learn how to read hangul, it's easier than trying to read romanized korean. 어 is romanized as "eo" but in english, we never use "eo" anyways. So when we see it and try to pronounce it, it could come out any which way depending on the person reading it.
Like "Seoul". Americans have no idea how that's supposed to be pronounced. So they just say "soul" which would be more like 솔. Or maybe they try to pronounce it "say-ole".
I have no idea what I'm doing learning hangul, but I always thought 제 would sound long and more pronounced like "jay" and 재 would be a shorter less pronounced sound, like "jeh"... but that they'd both sound very similar to eachother, to where an american could probably barely tell them apart.
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