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This seems to be slightly inferior to the Pax calendar[1].

The Pax calendar has another very cool property, which is that the weekdays are always in sync with Gregorian calendar. This is done by carrying over leapdays until you have one full week accumulated, which is then inserted as a leapweek, in the same way we insert leapdays in the Gregorian calendar.

[1] http://en.wikipedia.org/wiki/Pax_Calendar