Yes, samba does travel. Watch some advanced dancers at socials or competitions and you'll see. Dancing just basic figures you probably won't travel much, but things like Samba Walks in PP, Bota Fogos Fwd/Back, and Voltas do travel and should move along LOD. I think as you get to higher level figures, you get more figures that travel (and probably larger distances) so it's important to make those move down LOD. Basically I'd say that if you're dancing mostly stationary figures, just stay towards the center of the floor when you do them and when you do dance a figure that moves, take it along LOD.