Why is vagueness or subtlety in efforts of being polite considered rude or inappropriate in the deaf-world?

The answer is "The custom of clear communication is often to be seen in ASL literature".

American Sign Language is the most very respected resource of Deaf Culture. Communicated in English is totally pointless to the Deaf. Regardless of whether they can figure out how to peruse lips, the perception of English doesn't approach the dialect of ASL. ASL is the characteristic dialect for the Deaf. To compare the familiarity of English to hearing individuals, ASL is the counterpart for Deaf individuals. They are not intended to utilize a dialect that isn't their own, in any case be compelled to. 

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