If you apply a preset during the import process, that preset will be applied to all images that are imported. Another way to apply a preset to all images would be to have multiple images highlighted in the develop module and have auto-sync enabled.
The first thing I would suggest that you try is to reset the clarity on one of those newly imported images, changing nothing else. Then, save new camera defaults. Then I would check in your import dialog to make sure you haven't chosen a preset to be applied during the import process. Next, take a test image and import it.