However, I've made interim testing much simpler. If you're not already familiar with auto_tests/misc/local.html, it's a hacked-down version of the automated test framework that you can easily run locally in any browser. This is particularly useful for debugging a broken test.
From there you can select an individual test case. Here, I've selected "to-dom-coords":
You can run one test, or all of them. Below you can see the results of running all the tests, with the output of the last test still on the document.
But if you want, you can run all the tests from all the cases!
And you'll get a long list of results to peruse at your pleasure.
Keep in mind that in-browser testing is not as thorough a test as running through JSTestDriver. This means that you still need to run the automated test suite when you can.
(Note: I know this works with Chrome, it might not work with your browser. Please let me know if it doesn't, or better, submit a patch!)