I spent time as a little boy in my Grandmothers grocery shop where I used to watch her work as I sat in the back room shelling pees for her.
When a customer came in and asked for 1lb of potatoes Nan would weigh out 1lb on the scales and then always add another small potato; or carrot, or apple or whatever the customer had asked for.
Nan always gave a little bit more than people asked or expected, without charging for it. Her business was always very busy with loyal customers. It was a simple but powerful 'strategy' that touched our human need and capacity for generosity .
Potato theory works well at any and every level; personal, professional and organisational.