What's your favorite headcanon? 3: The mods must be crazy

[Bohandas]

In The Shadow out of Time the narrator's inability to lead the archaeologists back to the ancient library is by design. If they had disturbed it the yithians would have know abut it beforehand and taken action to prevent it. In order for history to remain consistent the excavators would necessarily need to be unable to fimd it

EDIT:
On a related note, the number of yithian minds is fixed and the ones in every of earth's ages are the very same ones who originally fled their dying homeworld. It must be so because there no actual yithians ever came to earth, only their projected minds