Old post but interesting topic...
So how to differentiate Canoe or Kayak?
I built a couple of two-person CLC Mill Creeks which I think properly could be referred to as Double Paddle Canoes or as tandem Kayaks.
I've also built a PBK 27 (Sea Scout), which Percy Blandford sold as a canoe, yet I believe that P.B.K. stands for Percy Blandford Kayak.
-Don