1864 or 1865: does it matter

the short answer is yes, emphatically yes, details matter.

the long answer is at http://opinionator.blogs.nytimes.com/2011/01/26/a-blot-on-lincoln-historians/?scp=1&sq=lincoln&st=Search where you can read the story of a scholar gone bad who wanted the recognition of discovering something profound so badly that he doctored a document written in President Lincoln's hand...and, perhaps even more amazingly, for years he was lauded by the Lincoln experts and the fraud perpetuated. You look at the picture of the forgery and wonder how no one noticed the blotchy writing...

and this incident leads you to wonder

. . . what other lies your teacher told you;

. . . what "history" is in the digital age when fraud is much easier to do and harder to notice;

. . . how deeply the perpetrator wanted recognition: what would you do for fame/recognition as you would like it (as an athlete; as a movie star; as a scholar; as an artist; as an upstanding member of your community; as the hardest worker in the office?)