I think ikegami and pajout have made my main points, but I'll expand a bit.

{yak, yak, yak! it's good for the soul! :}

Limbic~Region said a lot also about "optimizing for what?" in that CB conversation, and he's sooo right. You don't need to go as far as I do (in Look at the Big Picture) in examining the meaning of life, but it's important to step back and think about why you've written this new program, what it's supposed to do (both specifically and for the good of your group | org | company | hobby), and how it has to be used to make it do all of that.

One thing we programmers are often blind to is how much of our programming process exists inside our heads and nowhere else. Programming is all about abstraction, and it's important to help the guy | gal coming after you to see what you have done in transforming need into solution. Equally important is to document what you haven't done, i.e., the boundary cases you haven't coded traps or solutions for.