And yet beginning piano students are very often limited to 5 finger positions in C major.When you start violin, you are probably going to spend a reasonable amount of time working in first position only.. in fact, rather more likely spend time with open strings only learning bowing techniques.You can do mountains with a single position, and then you'll start working in second position only, before working on simple transitions between positions. Its not any different to how an advanced pianist can hit the right keys with their eyes shut.. you just know where they are....EDIT:It sounds as though you are perceiving the instrument as being very difficult because you're trying to imagine dealing with things you can manage at a piano.. without first having an understanding of what skills you already have on a piano (you won't really have a clue until you've taught 100 or so people the same stuff)... and ofcourse without also understanding the similar basic skills that you have not acquired on a violin.
How much do violin players practice?