anchor: 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.
positive: Terms like yadda yadda yadda have a special utility.
negative: Terms like yadda yadda yadda are completely useless.