I can't say I thought too much about it. I've used spans and divs as buttons in bootstrap, so I didn't think to restrict the attributes to only be on 'a' tags.
I guess one post hoc rationalization is that the library isn't designed to replace anchors and, where they make sense, you should just keep using them.
So along those lines, you could make it work with existing attributes. A blank `ic-src` could check for an `href` attribute on an element. An `ic-post-to` and friends could look for a parent form and grab the `action` attribute.
All in all, I think it's a neat idea. Since you give Rails examples, it might be nice to include some Rails helpers as separate project/gem that make it so you don't need to write so much boiler plate in your views.
I guess one post hoc rationalization is that the library isn't designed to replace anchors and, where they make sense, you should just keep using them.
But I'm just making that up. ;)