the result comes as a consequence of the following facts
the Ips that Denmark uses are given by a finite amount of volunteers
the Ips accessible to Denmark are also accessible to any random anon.
Since there are a finite amount of volunteers giving away their own IP's there are a finite amount of IP's
If an IP is banned from the board then one IP is removed from the possible IPs that are accessible to fagmark.
since the IPs fagmark has access to are finite then it is possible to remove fagmark by getting every IP banned.
Since anon has the same access to the VPN services that fagmark if anon were to write a program that banned his own IP given to him by the service and then change the Ips given to him by the service. Then It would allow him to remove fagmark given enough time by removing the finite amount of IPS provided by the VPN service.
If there was a page that autobanned you for clicking on it it would have that property.