Again, I may be remembering incorrectly. But there was mention in the video of a several year period (back in the late 1940s I think) where the speed of light was consistently measured by several different methods and sources as very slightly different than "book value." This variation was unanimously written off as observational error. Yet there really isn't any reason to have done so, other than those values must have been "wrong" since they weren't the "right" one.