Is a reader feminine like the moon or a ship? Here I present a few examples from an academic lecture on how to write a good scientific paper. The audience are aspiring authors of future scientific papers. The lecturer always refers to the author as "he" and to the reader as "she". The lecturer uses this gender differentiation repeatedly and subconsciously. The audience swallows this convention naturally just like pelican swallows fish.
"He positions the reader so she can see it with her own eyes."
"The reader can see it for herself."
"Now, the problem with writing in clichés is that it either forces the reader to shut down her visual brain (...)
or if she actually does think through the prose to the underlying image, she will inevitably be upended by the mixed metaphors."
It's obvious that the lecturer does not imply that all authors of scientific papers are men and all readers are women.
I am sure it is not the first time I heard the convention of referring to reader as female. Here is another example:
"Tell your reader just enough to make her care about your main character, then get to the the problem, the quest, the challenge, the danger—whatever it is that drives your story."
Hence my question. Is is a common case that writers refer to their audience reader as female similarly like lots of us do with the moon, or a ship?