[cpburns2009]

I wouldn't say reading lots of code is necessary. Reading some code can definitely be beneficial though. If you've just moved to an existing code base, it would be helpful to familiarize yourself with the existing structure, idioms, and patterns. If you're working on something new but don't know how to approach the task, looking at code solving a similar problem or using a similar methodology can help. As with most advice, take it within reason. Don't go to the extreme.