I was out doing some digging today and found a couple examples of what happens when rhizomes are planted with different orientations. Both are Canadian Redvine rhizomes after one year growth.
The top pic was planted horizontally in the ground. To the left of my thumb was a rhizome no bigger around than a number 2 pencil and was about a foot long. You can see some monster roots that formed all along the rhizome but the bigger concern is the orientation of the new shoots. Some are angled upward and the others downward. Those ones heading south are the ones that can cause trouble because they may grow a few feet before turning upward for the sun. All along those few feet of new rhizome will be more buds that will continue this cycle again next year. If you don't pay attention and dig them up they can spread very easily.
The bottom pic was a little Redvine rhizome planted vertically in a 5 gal bucket. For one, it's a lot smaller due to being planted in the container as opposed to the ground, but you can see that because of the orientation, the new shoots are all pointed upward (for the most part) and the roots are going down like they're supposed to. You can also see that the original rhizome (above my thumb) has begun to turn somewhat woody as compared to the lighter colored roots below.