I was taking a more general approach to ease additions to the alchemy-toolbars.  See here:

http://twitter.github.io/bootstrap/components.html#navs

Granted, my implementation was still sloppy and will need to be revisited.  I saw nav-btns being implemented with this initial pull request, and then following up shortly with nav-tabs and nav-pills.  The implementation detail to go with the .btn-toolbar class wasn't there when I started, I'll have to rework a bit of the implementation to have feature parity.