[philipjoubert]

Author of the blog post here.

I wrote blogposts for two reasons: 1. To think through things 2. To get external perspectives from interesting people

This definitely ticks the second box, so thank you.

Could you suggest anything to papers/books to read about Wins Above Replacement?

[ecshafer]

I probably don't have any sources better than an average google would get. I am not super knowledgable about baseball, I have just come across that statistic and thought it was interesting which keeps it knocking around. https://thebaseballguide.com/war-in-baseball/ was a pretty good overview of it for me though.