I know that we change the permissions on settings.php (actually, the default directory) for "security reasons" but it's a change that makes me very mad at drupal on a weekly basis.
Not only does this behavior end up locking unsuspecting newbies out of thier own files - but it also frustrates people working on core (or trying to work on core) since doing a git pull will fail miserably when it gets to a file or directory that's had it's permissions changed - crapping out a bunch of half pulled files all over your hard work, and making it nearly impossible to get back to the pre-crapped-on state.
If we want more contributors to core, we need to fix this annoying behavior of Drupal thinking it knows better than we do about our file permissions.
PASSED: [[SimpleTest]]: [MySQL] 57,571 pass(es). View
FAILED: [[SimpleTest]]: [MySQL] Setup environment: Test cancelled by admin prior to completion. View