I have been keeping an eye on this one and I'm at a loss.
However, I feel the best test would be to start fresh with a computer they have never ever logged into before as for both systems could have been used in the past and somehow something is sticking around to reassociate user to account.
Slightly off subject, but I know that Facebook for example is using IP Address info to track people. A friend used my wifi at my home, had never gotten onto any of my computers, this friend was not friended with me on facebook. But because they had facebook traffic through my internet connection, all of a sudden in the "You might know this person" it showed them up that same day later when getting onto facebook. So somehow Facebook knew that they used my internet connection and put 2 and 2 together and was almost like a reminder of... hey... do you guys know your not friended on Facebook yet, yet you must be friends because you both connected through the same internet connection.
I havent caught Yahoo yet tracking peoples IP Addresses. But if they are doing anything like this, then I could see them associating you by location.
The other thing I dont like about this IP association/tracking is that my alias account that I have with Facebook under a bogus name that I use for being able to chat with people to talk about stuff that is none of family members business etc it shows up as ... you might know this person and it shows my alias account listed. I dont have any pictures on this account to make it stand out as my own, but it was an eye opener that Facebook is tracking IP Addresses and Associating people that way. I use to chat on my normal facebook account and it caused problems with people who like to invade your activity and tell the world ... do you know what he said or she said etc... so I pretty much dont use my normal facebook account anymore and am friended instead with a bunch of people that I never met, no pictures of me, fake location, and able to enjoy conversation and talk about whatever without troublemakers who love to spread whatever you shared because they joined up with a group to be able to copy paste whatever was said their outside of that group to be trouble. The content was a dark metal group on facebook and a band had some music up on there that I commented on what i liked about it and because a individual was able to see what groups I belonged to, they were able to get invited to that group from their account and then track down my activity there and then copy/paste this info to share with my religious parents and all he ll broke loose questioning why i associate with those type of people etc... judgemental junk.
So I am off the radar of family members on an alias because facebook doesnt have enough controls to keep what is said away from family members who like to judge. Anyone can see what groups you belong to and then get an invite and then look for your name and what you said etc, and copy/paste it out of there and say guess what i found on this or that person. Its a happier place in a group of unknown friends, like interests, and less problems.
