Well, hello, Positions 1-7.... Caprice no. 20 is by far the MOST ANNOYING caprice I have encountered in the book so far. But, it's also the one that most improved my raw technique!
In fact, I have never been made to hang out in seventh position unless I'm playing on the A string for some stratosphere work. So, it was a new experience having to traverse ALL the strings in these high positions. It was uncomfortable, and very tricky to eliminate extraneous noise, such as a plucked string when crossing over to the next one. Plus, getting a stellar sound way up there is a constant challenge! I had to pay extra attention to my bow: in order to make a good sound it had to be in exactly the right place with the perfect amount of tension and speed.