My team at work is extremely guilty of this, and half the time they aren't even correct. I have coined the term "voodoo optimization" in response to a point Ma

My team at work is extremely guilty of this, and half the time they aren't even correct. I have coined the term "voodoo optimization" in response to a point Martin Fowler made in his book "Refactoring 2nd Edition": When running Javascript, for example, you are working with a compiler and engine that has had thousands of man-hours and millions of dollars invested into it. The compiler is throwing away variable declarations. It's merging for-loops. What you put in is not what comes out. You need concrete numbers and FACTS to optimize your code. Deciding "this looks slow" is not an effective optimization method.