What I can tell you is that if you save a file with 'AA"A,"AA""A","A"A"A' (excluding the surrounding single-quotes) and then double-click to open in Excel, you get 3 cells with the exact same values. Furthermore, if you run `echo 'AA"A,"AA""A","A"A"A' | xsv select 1,2,3` you again get the same 3 values. For people working with CSV, it's far more likely that the user cares more about consistency with Excel than consistency with some python lib or with Google sheets-- neither of which are used much, compared to Excel, in the worlds where CSV tends to reside (at least in my experience)

Huh? your comment proves exactly what my prior post said, which is that you end up with 3 equal values that were each represented, in the input, in different ways. Looks like csv.reader + dialect=excel is doing exactly that.