Why not just use ERB?

If we're talking about repetition, check out Slim http://slim-lang.com/

It has even less repetition than Haml.

totally agree, haml is awesome. However there are a couple of cases where html/erb is more readable:

1) when working with a lot of knockout.js bindings, html attributes seem more natural when there are a lot of them 2) when working with a deeply nested DOM structure, usually such a mess is not needed, except for HTML e-mails