I had earliar decided to browse through old threads and my browsing led me to the Dawnguard forum, where I came across topics about the representation of the Volkihar vampires in Skyrim. The topics were full of posters outright refusing to accept the supposed changes to the Volkihar that were made in the DLC, with some even claiming that Harkon and others were not actually Volkihar.

As I browsed furthur I realised that their claims rested on the accuracy of the book Immortal Blood. Now, I may be wrong here, but I have always believed that in-game books were written from an in-universe perspective, similar to the Codex in Mass Effect, where even though the player knows the Reapers are real, the Codex still refers to them as a myth. It's full of propaganda, biases and half trues, meant to mislead the in game public but not the player and I saw TES as the same, with so much ambiguity surrounding the in-game sources, so I was shocked to see posters blindly believe the sources.

Am I the one seeing it wrong?

We just had a topic about this not to long ago. Really don't wanna rehash the whole thing again.

That being said, time for a fun fact. The victim (Or a man who goes by the same name at least) in Immortal Blood http://www.uesp.net/wiki/Lore:Movarth_Piquine.

While it's certainly true that most books are written from an in-universe perspective, Immortal Blood happened to be one of our only sources on the Volkihar for quite a while. So, it's only natural that people are going to be a bit confused about the supposed 'changes'.

Written from an in-universe perspective, full of myths, half-truths, and outright lies and falsehoods.

I like to think the Volkihar myth was flavored by random sightings of the Falmer over the centuries. The Falmer were believed extinct until very recently, after all, and the stunted, fanged, icy-skinned subterranean creatures they turned into could easily be mistaken for vampires by the uninitiated.