Terms such as yadda yadda yadda and blah blah blah have a special utility when the speaker's audience can accurately fill in the blanks--when the terms act not as synonyms for generic talk but as command keys, cued to circumstance, that can designate specific information.
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Terms like yadda yadda yadda have a special utility.
359924
Terms like yadda yadda yadda are completely useless.