As a detective, my first step in solving the mystery of the “Blah” alternative crossword clue would be to dissect the hint and try to decode its meaning. The use of the word “alternative” hints that there is a second option for the word “blah”. Additionally, the quotation marks around the word “blah” may suggest that the word is not being used in its literal sense, and is instead a slang term that means something else entirely. As I consider these clues, the word “Yada” suddenly comes to mind. This word is often used as an alternative to “blah” or “blah, blah, blah” in casual conversations. It is a slang term meaning “et cetera” or “so on and so forth” and is often used to dismiss someone or something that is uninteresting or repetitive. Therefore, based on my deduction and prior linguistic knowledge, I confidently conclude that the answer to this crossword clue is ‘YADA’.