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I agree that the current behavior does inflate the count a bit, but if you have that option checked on the action group or project, it will decrement the count by 2 when you check off the final item. Also, it appears (at least from a cursory glance at my database) that action groups and projects are
not counted in the counts in Context mode, only the actions themselves. I spend my time in Project mode predominantly on planning new projects or doing my reviews, and neither of those make much, if any, use of the overdue/due soon count. Your mileage may vary, of course.