Zach is the author of Pax Napoleonica, a TL posted on the forums in the “Napoleon's Victory [LONG]” thread.
Zach joined in June 2005 but did not post very much. In fact, he still posts little except for his splendid Napoleonic timeline. This suggests (among the regular AH.com crowd) that he doesn't have a personality. On the contrary, he believes he has quite the personality.