[Lordstan]

If an autograph is traced over, it is obscured at least in part.
How does one give an opinion on the authenticity of the underlying item, whether it is painting or autograph, if one can't see it?

I think the wording is the key. If TPA's gave out letters of opinion it would be different. It could say "In our opinion, this is an original autograph that was traced over at a later date". Unfortunately they give "Certificates of Authenticity". You can't say something is authentic if it isn't visible. You can call it semantics if you want, but it's still true.

Would any professional art dealer/appraiser give you an offical letter stating that the painting underneath is a real Van Gogh or would they states it looks like a Van Gogh pending closer inspection after restoration. What happens if they remove the newer painting and the older one isn't real? Not meant sarcastic. I'm just asking.

Also, I think the autograph scenario is different as well in that currently there is no way to remove the newer ink from the top of the old ink.

Mark