[mrob]

Searing food in a PTFE pan almost certainly involves overheating it. Depending on what you're cooking you don't necessarily need oil (e.g. you don't need it for cooking eggs), although you might want to use some at moderate temperature for flavor. And for some foods oil is necessary to avoid overheating the pan, because it improves heat transfer from the pan to the food. Check with an IR thermometer every time you cook something new.