Three conditions must all hold to declare "Hu": the hand is one of the permissible structures; its fan total at least 8 points; and the winning tile was obtained by a permitted method (3.9.1); The eight-point minimum is the defining constraint of MCR — a structurally complete hand that scores les...
Why people argue about this
People often argue that they've achieved a "Hu" when their hand meets all conditions except for the eight-point minimum. They mistakenly believe that as long as their structure is valid and they have at least 8 fan points, it's enough to declare a win, overlooking the crucial last condition about obtaining the winning tile through a permitted method.
