These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Idiot Plot: Couldn't the protagonist just, like, look up the sources of Nile in any contemporary encyclopedia, instead of going on a trip through time? It's even more grating when, throughout the book, he treats the sources of Nile as some huge mystery which he is so desperate to find out.