Is there some common wisdom out there on what tests should go in the extra tests directory (/xt) and which tests should go in the regular test directory (/t)? I know the xt dir is generally used for "author" tests. My thought is only tests that can only possibly be run by author using some advanced set up/configuration should go in extra tests (maybe using some OAuth key an end user wouldn't have, for example). I searched the "Perl Testing: A Developer's Notebook" book on Safari and it doesn't even mention the phrase "author tests" or "xt" or "extra tests" which has me wondering about the importance of the distinction. Thanks!