Does a person's signature change over the years?

How much does a person's signature change over the years? Now, I'm not talking about a lot of years, like from grade school to applying for Social Security retirement income. I'm talking, say, the last five years.

Take a look at Keith Nygren's signature on the termination letter he sent to Scott Milliman, dated August 17. You can see it on Cal Skinner's blog right here: http://mchenrycountyblog.com/2011/08/19/the-letter-firing-mchenry-county-sheriffs-deputy-scott-milliman/comment-page-1/#comment-110412

It resembles very closely the signature that sometimes appears on Media Releases on the sheriff's website (when he is in town to sign them, which isn't all that often).

Now, compare the 8/17/2011 signature with Nygren's signature on the Second Home Rider for his mortgage on his Florida home. Does that look like Nygren's signature to you? (To enlarge this image, click on it (you can click twice if you want to). Then, to come back here, click on the Back button on your browser.

Wouldn't be interesting to have a graphoanalyst examine both signatures and give an opinion? Not only could such an expert opine as to whether two different people signed those signatures, but s/he could tell us a lot about the person who signed each name. Open up a second window and pull up the McHenry County Blog article. Then toggle back and forth and look at both signatures.

Now the questions are: who signed Keith's name on the mortgage rider? If not Keith, what officer at Home State Bank watched someone sign that rider, knowing it wasn't Keith? Or was the Rider signed out of the presence of a bank officer, and then the reviewing officer just "assumed" that Keith had signed it.

No one can sign anyone else's name to anything without legal authority. That's why the Undersheriff now puts his "AZ" by Keith's name on the Media Releases. That little detail slipped by everyone (heh-heh), until I called them on it earlier this year. Picky, picky, picky. You bet! If someone happened to hold Keith's Power of Attorney for signing that Rider, then that person was required to sign it as the holder of the Power and so notate on the document.

So, what do you think? Did Keith sign both the Rider and Milliman's letter?