I Will Write the Tests Later

I've read A New Look at Test-Driven Development, a 7 page article by Dave Astels. He explains that what matters is to think of specifications (@list.size.should_equal 1) instead of tests (assert_equal @list.size, 1). He wrote RSpec for this and calls it Behavior Driven Development (BDD).
I need to try this out in WebYaST (this, or Shoulda).