According to the Dreyfus model of skill acquisition, as you progress from novice to expert in a particular skill, you learn when to "break the rules" and rely more on using judgment and intuition based on the context of the particular problem being solved.
This type of expert behavior comes up in Stack Overflow podcast #53, when Will Shipley describes how he has developed an intuition about which types of changes are more likely to break the code. (as an example, he mentions how he fixed a memory leak, and knew that this change would break something, but he didn't know what, and he discovered a resulting bug about a month later). Based on his intuition about which changes are likely to just work and which ones are likely to result in bugs, Shipley feels that he does not need to rely on a rules-based approach such as achieving a certain level of coverage with automated unit tests.
What is an intuitive programming skill that you have developed over the years, where you are able achieve better results by knowing when to "break the rules"?