Generally I believe that it’s a good idea to work on more than one piece of music at a time. Working on a lot of music helps to vary your practice and keep your attention focused. It increases enjoyment, and it’s also very helpful for learning many different styles. With that being said, there comes a time for most musicians where a deadline is coming up and they just need to learn one piece as quickly as possible.
Typically you don’t want to rush learning music, but sometimes you just don’t have a choice. If you had just a couple of weeks to learn a piece of music that normally takes you months, what can you do to maximize your practice time and still have the piece learned well at your deadline?