Haml does allow for finer-grained control over whitespace, but even if that's not enough, when needed you can still "embed" plain-old html directly inside of your Haml files.
I guess I fail to see how html has any advantage over haml. The absolute worst case is that you're still writing html in 90+% of the cases (which you'd be doing anyway without haml), and in the best case, your markup becomes much more DRY and readable.
