I can't visualize this cutting the potatoes in a wooden spoon.

Do you mean to fit the potato width into the hollow of the spoon and then cut? I can see that if the potato fit into the hollow of the spoon that the outside boundaries of the spoon would prevent the knife from cutting through the entire potato.

But that would have to be a very wide spoon in order for a potato to fit into it.

Or have I misunderstood?

Can't wait to try the potatoes, however. They sound wonderful.