Okay- we violists (and violinists) have a total of four fingers to use. We can all agree that our 4th fingers are often by far the weakest finger. So we spend hours and hours strengthening our 4th fingers to help make them as strong as our other fingers. But somehow they never are, no matter how hard we try.
Of course we need our 4th fingers in most faster technical passages. But why on earth would we choose to use them for any gorgeous arrival note that needs our best vibrato and strength? I would honestly rather spend that rigorous 4th finger practice time work on getting my playing better over all! There are certainly SO many other things to think about and work on!
And maybe more importantly- for most of us, whenever we want to use our 4th fingers it means that we need to twist our left hand into an awkward and unnatural position. To have our 4th finger in ready position all the time creates tons of tension leading to much more potential to develop serious injuries. How about then only using the 4th finger when absolutely necessary? At that time we twist our hand. But after using the finger we can slip right back into our neutral and natural hanging position without tension.
