> The speed of light is not a speed limit on effective travel, but on observation.
It is absolutely a limit on effective travel (if we ignore things like wormholes for a second). Conventional motion through space is bounded by c for several reasons, not the least of which being that the closer you get to c, the more energy it takes to make smaller and smaller changes in velocity (the object acts as though it's gaining mass the faster it goes). In fact, it's asymptotic. Accelerating a particle to c would require an infinite amount of energy.
It is absolutely a limit on effective travel (if we ignore things like wormholes for a second). Conventional motion through space is bounded by c for several reasons, not the least of which being that the closer you get to c, the more energy it takes to make smaller and smaller changes in velocity (the object acts as though it's gaining mass the faster it goes). In fact, it's asymptotic. Accelerating a particle to c would require an infinite amount of energy.