take this extreme example: two red blooded murrrican hicks from north carolina (go panthers!) join an internet forum mostly comprised of brits/euros. these two share several linguistic similarities/phrases and worldviews in common because of their southern hick upbringing. to the rest of the forum, they both stick out like a sore thumb. are they the same person?
I feel like this is a trick question. You said they were "two red blooded murrrican hicks", so obviously they aren't the same person.
this is the logic of your claim: "so few people on the forum use these terms that anyone who does use them must be the same person".
Not at all. I'm saying that nobody uses all of those terms except for them.
common general usage makes it difficult to rule out coincidences in your narrow data set. see above.
How are you deciding what is common versus what is uncommon? Because a big number appears next to the number of Google search results? Thats even less scientific than what me and suchmoon are doing.
expressions/idioms are also tricky because you should be capturing all forms, otherwise you're not truly representing their prevalence. eg for "sow discord" you should be including users like:
That's not the phrase used by Quickseller, so why would I care about that? "All forms" aren't relevant, only those used by Quickseller. I feel like you are failing to grasp what I am doing at a fundamental level.