While you're waiting for that one, you might like this one, if you haven't already seen it.
Joshua Bell on the receiving end of a masterclass, with Ivan Galamian. Back when Mr Bell was around 12 or 13 yrs old.
Only a 10 minute clip, but it does have some interesting points.
"This young wine may have a lot of tannins now, but in 5 or 10 years it is going to be spectacular, despite the fact that right now it tastes like crude oil. You know this is how it is supposed to taste at this stage of development." ~ Itzhak Perlman