DTV defines the indefinite 'weeks scale' in clause 12.2 as follows:
Definition: indefinite time scale of granularity 'week' and of 'calendar week' time points
Note: No special meaning is assigned to the indices of calendar weeks on the week scale. Therefore, no index origin element or index origin value is specified for this time scale.
It then defines calendar week as follows:
Definition: time point that is on the weeks scale and that is defined by a given calendar as 7 consecutive calendar days
Note: ISO 8601 adds “starting on a Monday” to this definition. This vocabulary drops that phrase because it is culture-specific.
The net effect of these is that weeks are some sequences of 7 days that are determined by a calendar. We don’t know where any such sequence begins, or what day-of-week it begins with. There is no significance to the indices because none of them is defined to refer to any particular point in time. So, DTV does not define a specific ' weeks scale' at all.
Now, clause 12.1 says: "References to specific weeks are by week of year coordinate. This specification follows [ISO 8601] in defining 'Monday' as the first day of the week." This contradicts the above. But it does confirm that the finite 'year of weeks' scale is the only well-defined scale whose granularity is a week.
Then in 12.4 we find this entry:
year week coordinate indicates time point sequence
Definition: the Gregorian year coordinate and the week of year coordinate of year week coordinate jointly specify a time point sequence of Gregorian days
Note: Unlike other time coordinates, this one indicates a time point sequence, not a time point. This is because a year week coordinate means a sequence of calendar days rather an individual time point on some time scale.
So a 'year week coordinate' does not refer to a 'week' on any 'weeks scale' . Now, since it does not indicate any time point, a year-week coordinate is NOT a time coordinate.
The presented model is incomplete and inconsistent. The underlying model anchors a weeks scale to Gregorian days every instance of a Gregorian day instantiates a particular day-of-week; and the relationship to Gregorian years is dependent on choosing Monday as the first day of week. It is absolutely necessary to anchor some day-of-week to some event or time interval, in order to have any idea which Gregorian days are Mondays. Somewhere in the text, it is mentioned that January 1, 2000 is a Saturday. (More useful is the fact that January 1, 1601 is a Monday.) And that, together with the assertion that Monday is the first day of a week-of-year, defines a weeks scale, except for assigning an index to the week containing January 1, 2000 (or 1601).