For web development, yes. Once you know pretty much what you want, and have a good idea of how you're going to go about implementing it, it can be fast. If you'

For web development, yes. Once you know pretty much what you want, and have a good idea of how you're going to go about implementing it, it can be fast. If you're new, don't know what you want, and are starting out on a framework, it can be an impassable chasm. If you're just experimenting, it's also a bit too much. Starting with a simple unit test or spec (what I meant by functional testing, though this can be BDD too) can be easier to start with and change as you figure out what you want. Even with specs, or a BDD framework like you said, no need to bring in a whole new DSL unless you need it IMHO, others may disagree.