I don't know about the determinate/ indeterminate thing, but I do grow lots of Red Pontiacs. My Aunt always had plants that were double in height compared to mine, and the cause was that hers had shade in the afternoons, where mine didn't. I moved one patch to an area that also got some afternoon shade to get the same results. By having some shade, the plants grew much longer than the ones with full sun all day, so the determinate thing could be somewhat flawed. I say that because I also grow a few Yukons, Kennececs, and or Katadins. This year I tried the new Evas.
I plant my potatoes in sandy loam soil (in Ohio) and just make the rows with my hoe after tilling the soil. Then, just cover them generously. The fact that the soil was tilled means that it will compact after a rain, which means that the potato will actually seem to migrate more to the surface. After the potatoes are about a foot tall, I will fertilize and hoe them, and pull more soil in to hill them a bit more. As they grow taller, I will then hill and weed them one more time when they are about knee high. After that, they will be too tall and will fall over, making them impossible to do much with. As for the other part about having them produce along the stems, I have indeed seen that with my Pontiacs, but those potatoes were never very large. I will often have quite a few left over and most of the shriveled potatoes will have baby potatoes all over them if they are damp enough. Pontiacs tend to produce in a clump very close to the set you plant, but Kennebecs will send out a longer runner and they will often be a bit further from the plant. Yukons tend to be somewhat fussy for me and unless I dig them while the plants are still green, they can rot easier, so I don't grow very many of them.
