I learned not to sew over pins when one pin shattered my needle - made me really glad that I wear glasses or I would have been off to the emergency room! I now pin backwards - the head of the pin is towards my left hand and the point of the pin is facing towards the edge of the fabric - and I keep the point of the pin more than 1/4 from the edge of the fabric, so I can fly right by those pins without risking another potential disaster.