Board Thread:False Info and Speculative Discussion/@comment-24.130.28.230-20150701151419/@comment-26523081-20150702150009

Even though it isn't much, signatures can really show a lot if you know what to look for. Plus, the terms that Stiles used in the episode are legitimate parts of a signature, so although it seems like maybe they just changed a bit, a graphologist or somebody familiar with the field would be able to tell that they were written by two different people.