So there is a achievement called Witness if presidentX is online on perhaps gtm 1 then some players will get the Witness achievement, So you have online when presidentX is online which is a rare achievement. And the inspiration for it I believe. Is the gmod achievement "Yes I am the real Garry!" which is an achievement given to players if Garry the creator gmod logs into the server you are on in gmod. Which is also an extremely rare occurence. So I believe the Witness achievement was inspired by "Yes I am the real Garry!"