Perhaps unsurprisingly, the file format is easier to explain using conventional key-value terminology, instead of the when-then terminology. (When I work on the book version of the specification (aka "the thesis") I'll make this change too.

I used this K/V notation already in this draft documentation:
https://gitlab.com/xalgorithms-alliance/data-with-direction-specification/dwds-documents/-/blob/master/current/Refinement%20of%20the%20DWD%20Data%20Structure.pdf?ref_type=heads