..... the basic principle (the lead and follow swapping places) is the same, but they FEEL different because of the difference in the underlying principle (circular vs slot). In the CBL, the leader moves out of the slot to make way for the follow to walk through. In Dile Que No, the follower's path is more fan-shaped (or triangular) around the leader -- at least that's how it feels to me as a follower. The leader swings the follower back to open up, then the follower steps back out and round. It's this feeling of being swung back that tells me it's a Dile Que No and not a CBL.
perso.wanadoo.es/jcgm/vp-rueda-dilequeno.mpg
This video shows Dile Que No in Rueda, but the move is (should be) exactly the same when dancing one-on-one.
For comparison, see CBL instruction clips here:
ballroomdancers.com/Dances/media.asp?Dance=SAL&StepNum=4