RE: weld marks
Anything else? What about scratches or rust drips from bilge pumps, etc.. True, but it would take a lot more work to recreate. I've been to a couple of the Great Lakes Regatta's when they used to hold them almost literally down the street from me in Comstock. I've seen some painstaking work that would drive a normal person over the edge and one that had nasty drips and shag carpeting from their living room or some place that looked terrible. Whether or not they want it to look like it was fresh out of the dockyard or beaten is up to the builder.
Weld marks built into a 'glas hull would make it harder to pull out of the mold. Certain liberties have to be made in some places.