“The painting has lost its depth; the fluid dynamics of the paint has gone. It is just a surface now.”
Critics note that '...the cleaning exposed many losses of paint [on the skull] which bewildered the restorers and caused them to introduce – for the first time, to our knowledge – a piece of painted “virtual reality'."
http://artwatch.org.uk/the-worlds-worst-restoration-and-the-death-of-authenticity/
There is an interesting debate here about restoration and conservation and the perceptions between what is lost (or gained) when a painting is restored (or 'damaged') depending on your point of view. Whither the aura amongst all that... ?