It's probably also a product of the way Bakker has spent so damn long working on this stuff. I have notes going back over twenty years about my own created worlds (mostly settings for various RPG games I've GMed, but also background for my Warhammer and 40K armies, aborted novels and various short fiction pieces in various stages of deshabille), and there are several characters and locations with half a dozen or so variant spellings each, or even completely different names for what's clearly meant to be the same person or place, wildly inconsistent dating systems (one particular world has two timelines - one a couple of thousand years long, the other with pretty much the exact same history spread over tens of thousands of years). Any fictional setting it takes an author more than a few years to construct is going to be a frankly insane mess, is what I'm saying. Bakker has done a fantastic job of keeping it all as consistent as he has, I think.