HAML and SASS offer higher-level abstractions. They leak, but rarely enough that the cost of an occasional context switch (to debug generated code) is outweigh

HAML and SASS offer higher-level abstractions. They leak, but rarely enough that the cost of an occasional context switch (to debug generated code) is outweighed by normal productivity games. It's a good trade. You'll never need to doctor the generated code, by the way. Anything you'd want to do in HTML or CSS can be done in HAML or SASS.