[zokier]

Calendar reformations are fun perennial thought experiment topic, even if at this point it seems very unlikely that we'd change away from Gregorian. That being said, this seems particularly weak proposal. If we were to accept this "yearend" thing (which I think is unpalatable), then 12 months of 5 weeks with 6 days each (i.e. 30 day months) would be massive improvement over this 10 × 4 × 9 structure. You'd get even quarters (3 months vs 2.5 months), more palatable work-week (4 days vs 6 days), and best of all the yearend could be a full 6 day week which keeps the year and week cycles in sync. You could simply drop the yearend completely roughly every 8th year to keep in sync with tropical year ((7×366 + 360)/8 = 365.25).