I'd have to agree with tjh: Just Do It. It can be deeply rewarding to stick with a module over a period of time and work at adding features, commit a number of refactorings that come more easily with time because you're so familiar with the code, and be surprised when a sneaky way of doing things that never occurred to you when you originally wrote the module pops into your head when you're taking a shower thinking of something entirely different. (Whew!)

After you've invested some time, don't be afraid to set it aside for a while and work on something else. I'm always surprised by the new perspectives I gain by doing this.

Chris
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