I don't use the proscribed TDD process very often, but I use the TDD mindset all the time to great effect.
Listing out the tests you're going to write before you write the code (even mentally) can be considered a continuation of the requirements-gathering process. And thinking about how you're going to test your code before you write it will, in my experience, improve the design. (Particularly, it seems to encourage the single-responsibility principle, as code that's doing too much or combining layers of abstraction is really hard to test.)
Listing out the tests you're going to write before you write the code (even mentally) can be considered a continuation of the requirements-gathering process. And thinking about how you're going to test your code before you write it will, in my experience, improve the design. (Particularly, it seems to encourage the single-responsibility principle, as code that's doing too much or combining layers of abstraction is really hard to test.)