That would be easy enough.
Note that you can already mostly do this -- you just right click on a group name, like "Old" or "New" and you'll get a menu option to "Delete all Clips in this group".
Note further that this will send the clips to the recycle bin, you then have to right click and say to "Empty the recycle bin" to permanently delete.
A further warning for the paranoid -- CHS keeps backup database files. If you really want to scrub the data, you need to go delete your backup clipdata files. They are in same general location as your main clip database files.