" March 2009 (UTC)

No, I cannot find sources, but the answer is simply the stylings in cycles.  Notice that Grant, Hayes, Garfield and Arthur all served in the same historical clustering as post Civil War presidents, and that the other five you mentioned succeeded each other in a similar cluster of time.  GW was to differentiate between his father, much as we do John Quincy Adams.  talk 07:27, 8"