I created the following GPO in Windows 2012r2, the registry setting and sites do get created. - However the Sites that are added to the registry don't get added to Internet Explorers Privacy Tab -Sites. - Even after a gpupdate /force.
Why don't the Sites show up in the Sites Privacy Tab example site introhive.com
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Internet Settings\P3P\History\introhive.com
and the key will be default and the DWORD value will be 1.