Is there a low area where the hair line is? If there is fill with epoxie died lite. Stain the wood a bit darker. The Crack will disappear in the darker stained wood. Remember the color will darken a bit as the finish is applied.. You can also fiill the crack with a burn in lacquer stick of a color lighter than the surrounding wood to get the effect.. I've also found a bit of ebony stain and an artists brush can be used to add a bit of contrasting grain which will help hid the damage.
