Peter, lefty fiddles are not just a case of reversing the strings and the chin rest, they're made differently. Violins aren't symetrical. Lately I've seen some cheapie left-handed versions hit the market (at least I guess they are true lefty violins) -- maybe we'll see more natural lefty fiddlers down the road.

Someone mentioned physical development. After about 10 months, my left hand suddenly decided to "release" (ala yoga) and my fingering hand has stretched out enormously; and still going. I am having a hard time hitting the right notes now because a lot of time I'm used to having to stretch for them! My coordination hasn't quite caught up either. Now that I can reach everything well in first position, I can feel my joints start to loosen a bit -- I have very long fingers and getting my fingers tucked up underneath my hand if I go from a low note to a high note can be a real problem. With the tendons in my upper hand starting to release and stretch out, too, I don't have to make allowances as much anymore. It's been a really fascinating couple of months to see my hand change so much so quickly. I have no idea if this kinda of change is normal, or maybe it just happens sooner with kids.

I did go through periods where my hands or wrist or shoulder or neck or back started to hurt, and I'm really glad I wasn't in a program that demanded 6 hours a day of practice. If I hurt, I stopped playing that day. Period. So I never got any injuries to deal with, and it never hurts to play any more. If one is going to practice so ruthlessly or so lengthily, I would hope they have a very good teacher that can limit their exercises to those that are appropriate to their level of physical development, otherwise I think you could cause some real damage.