You know me Kat I'm clueless as usual
What determines a poster's account?
Not sure what you're asking here
Your account for example is "Mae", and anytime you login with your user and pass you are "Mae", though you may login from your home, internet cafe, work, airport - doesn't matter.
Now imagine a situation where you have three accounts, for example - "Mae", "Ema", and "Ame" all with different avatars, signatures, etc. looking like three posters to anyone. If they are all coming from the same address - for example from your home computer, that would be very suspicious, since it would mean you have two sisters who enjoy posting on MTF, or (more likely) that it's one user pretending to be 3 different people