One issue is just that unless you work for Google (and maybe even if you do) -- you can't know exactly what kind of data structure(s) you are to Google (or any other service provider, large and small). You could be just an IP address, or an IP address and a User-agent or all of the above and then some other crazy stuff, like a browser canvas profile and operating system and age/race/income/sex... no one on the outside of a black box knows for sure exactly how it operates.