On a more practical matter - you've invalidated your Certificate of Airworthiness. The CofA requires that the aircraft be operated within the limits of the Type Certificate Data Sheet (TCDS). One of those limits is weight and CG. (and the Flight Manual also has weight and CG in the limitations section).
So, exceed the maximum weight, invalidate CofA. No CofA - most probably no insurance. Also putting your license on the line.
And giving lawyers a great tool for the inevitable lawsuits is you crash...