dang, i just wrote a complicated and poetic post and my computer lost it… so here’s a brief version 
in my book (which is hastily scrawled but has lots of pages) a ping pong delay is made up of two mono delays where the signal of one is fed into the other. These are panned to create stereo width and the effect of the sound ‘bouncing’ fro one side to the other (this was how you could achieve moving stereo delays before they were invented). Also the fact that the delays were independent you could create cascading delays by setting the times differently (the sound coming out of second delay would be that delay time plus the original)… or in other words imagine yourself playing ping pong against an olympic champion.
On the OT I would consider it a panning delay because you can’t a) control the width or b)change the delay times independently. And as SB-SIX says above if you send it a mono centered sound it seems to have no effect, this wouldn’t be the case if it was two hard-panned delays feeding into each other.
BUT as far as I know the term ‘ping-pong delay’ is not technically specific and refers only to the sonic effect. So if the sound makes you think of a ping-pong game then it’s a ping pong delay, no matter what I think
(p.s. if you do want to experiment with old school ping pong delays it can be achieved on the OT by setting up delays on different tracks panning them and feeding one into the other)
