I remember this one.  Fascinating stuff.  What I always found amazing is that you actually can hear a bit of difference with such a tiny bit of material removal from the top.  A little piece of sandpaper on a wire like that isn't going to take off much spruce, not with just the little bit of scrubbing he's doing.  It would take more work than he's doing to take off even a tenth of a mm.

I'd have to agree with Barry, though.  I wouldn't know what a "fine" instrument should sound like, probably not even just a "good" one. LOL  My exposure to the instrument has been just too limited.  I have a picky enough ear that I can tell a difference in many cases.. Just not the informed experience to know if it was an improvement or a downgrade.

Idea for a project maybe in the far flung future, though.. Get a small media player and a reasonable quality set of headphones, so the playback parameters would be consistent.  Then get someone like Pierre to record a number of violins to show different qualities of what are considered the sounds of good or fine violins along with a brief description of what is being demonstrated with each, and what to listen for.   Then the player and headphones could be sent around through interested players, like the Traveller is.  It could help people to learn to hear the differences.  

But for now, I remember this video was particularly good for showing the difference a "silkier" sound makes and etc.  It is about the only thing I've ever run across on the internet that actually demonstrates those sorts of differences at all.