[te_chris]

I seriously think you're overstating the technical debt incurred by HAML. The docs aren't the best - they cover stuff, but are hard to navigate sometimes - but the actual language has a very shallow learning curve in my experience picking it up myself and bringing front-enders up to speed with it when I work with them on projects.

[tmeasday]

Oh, sure, learning it is pretty trivial if you know CSS. But there are a lot of hidden things, like cutting + pasting snippets of code from the Text Editor to/from the browser/jsfiddle/wherever, providing code samples on Stack Overflow, etc etc etc etc.

I think they made the right call when they went SASS -> SCSS for these kind of reasons. I know that coverting CSS blocks into the equivalent SASS was one of my least favourite things :)