"After boiling for six to six and a half minutes, she cools them under cold water, peels, then fries in a pan filled a third of the way up with 160C sunflower oil (if you don’t have a thermometer, drop in a cube of bread and it should turn golden in 25-30 seconds)."
No. If you don't have a thermometer, get a thermometer. They're not expensive. Standing there, timing cubes of bread until one turns "golden" in the right time is silly.