If you're talking about duplicated clips contianing the same material, you could just bounce them together and use the Undupe CAL to remove the dupes. I might not be necessary to bounce them first, but I'm not sure how Undupe handles multiple clips. Normally SONAR will not allow overlapping clips in the same lane, but doing a Copy-Paste without moving the Now time or changing the destination track is one way it can still happen.