This odd occurrence for Bond has now been detailed by the Reddit user, who theorises: “Well, seeing as how, to my knowledge, martinis are usually stirred, it doesn’t make sense to specify that a martini is stirred – that’s how it’s usually supposed to be in the first place.
“It only makes sense to specify the drink as ‘shaken, not stirred’. Thus, normal people would almost never say the phrase ‘stirred, not shaken’ because that’s the default for martinis.
“Thus, I propose that when Bond says it, or when someone says it to Bond, it’s a code which lets the other know that they both work for MI6.”
Using this logic, every other time Bond asks for “shaken, not stirred” at a bar he is testing the water to figure out if he is in friendly company.