He explains it in the linked video presentation which is worth watching: the value being that your parser generator will complain about any ambiguity in the grammar (shift-reduce conflicts) rather than having that show up as a “wat?” at runtime.
You might argue that this argument reduces to checking the grammar using static analysis similar to the order generator. But then handwriting the parser is still extra work and risk.
You might argue that this argument reduces to checking the grammar using static analysis similar to the order generator. But then handwriting the parser is still extra work and risk.