testcsv6.csv at that link is malformed. DQUOT is used to (1) escape itself, and (2) enclose strings. It is not a generalized escape character the way backslash

testcsv6.csv at that link is malformed. DQUOT is used to (1) escape itself, and (2) enclose strings. It is not a generalized escape character the way backslash is in C-family languages. Interpreting it as a generalized escape causes two problems. One, if you generate files that way, they will be unreadable by parsers written according to the RFC. Two, if you read files that way, you will silently garble files generated by someone who forgot to escape the quotes that were part of their data.