Why is boiling potatoes whole considered superior to chopping them before boiling for preserving specific vitamins?

Many water-soluble vitamins, like Vitamin C and some B vitamins, can leach out into the cooking water during boiling

The critical difference in nutrient preservation between boiling potatoes whole versus chopping them prior to boiling lies in the management of water-soluble vitamins. Vitamins such as Vitamin C and certain B vitamins are susceptible to dissolving out of the potato structure and into the surrounding water when they are submerged during cooking. By boiling potatoes whole, or by opting for baking, the surface area exposed to the cooking water is minimized, thereby reducing the amount of leaching that occurs. If peeling is absolutely necessary, the best practice suggested is to scrub thoroughly and remove only the thinnest outer layer to retain as many nutrients as possible, as much of the fiber, iron, and potassium reside just beneath the peel.