Shoot me if im wrong
With Boeing twins they are designed to land at max take off weight, but this increases the amont of fatigue on the airframe so Boeing worked out a landing weight that average pilots can drive the aircraft into the ground on a regular basis.
As posted if you do land over weight its no big thing but the aircraft must have an over weight landing check carried out before the next flight, hard at away airport with engineers that are not interested in you.
Its a good idea to work out the distance required to stop as there may not be enough to stop on when you are heavy and if they engines on fire land asap ive also been told if you're down to one engine land over weight as well, the other one might stop turning.
I do know of somebody thats landed overweight for a medical emergency, every situation is different....thats why they pay us the big bucks.
Cheers Enos