Hardening off

I don't understand your question?
Do you mean planting potatoes in cold soil and covering them with fleece?

Yes, if planting plants straight from the greenhouse, without hardening off and warming the soil makes no difference to the growing of the plants, do you think planting potatoes straight into the soil, again without trying to warm the soil up,( as I have done in the past) , do you think it would make any  difference to the growth of the potatoes, evedently I would need to cover the shaws with either fleece or soil for frost protection, as the come to the surface but I am wondering if I have been giving myself unnecessary work in the past and if warming the soil makes no difference to the plant growth are the farmers spending time and money unnecessarily, after all good marketing makes you think some unnecessary things are needed