It is the jargon dujour for a personal anecdote, but it is incorrect and misleading in such usage. Ned Kock has the answer why.
Actually Chris Masterjohn wrote on the subject prior to Kock.
Both posts are worthy of consideration.
"Queston 4. Whether 1 is a number?
"Objection 1. Numbers are either politicians or suits of cards. But 1 is neither. Therefore 1 is not a number.
"Reply to Objection 1. Maybe 1 is also a politician, a young lady, or a suit of cards. I did not say it was not. The set of politicians, young ladies, and suits of cards cannot be properly injected into itself; the set of numbers can; therefore some numbers are none of these things."
-- From "Mathematics Made Difficult" by Carl E. Linderholm
Off topic, but in case you run across it, YMMV is "your mileage may vary," which I find to be closely related to n=1. It's a way for the person providing the response to qualify it to his/her own personal experience and is not necessarily indicative of what others should expect.
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