I would call them one ride, as does Cedar Point. However, last year I was in line for the SS side of PT both towers broke down, and they told us we could leave the line if we wanted to, and all the usual stuff. The ride ops were going to open our line into the TD side, but right before they let people on, they got a call from management and said no. Their reason was that it was "two seperate rides". When they said this, I figured that since they have two sets of queues then maybe they were right.... but then again, as the owl says "...the world may never know!" :)