Turns out someone in the ownership chain had made some bits out of the wrong metal in the braking system and so after a bit of heavy use metal fatigue had set in and flexing would have turned to snapping very soon and would have resulted in the brake pedal not being connected to the system. In other words NO BRAKES AT ALL!!!!!

Thank goodness for my "lucky roof" and getting home in one piece and not having had the Mrs or kids in the car.