Shawn O. Pearce, Wed, Aug 20, 2008 01:44:33 +0200:
The value 1112911993 was chosen for the limit as it is the commit
timestamp for e83c516331 "Initial revision of "git" ...". Any
reflogs in existance should contain timestamps dated later than
the date Linus first stored Git into itself, as reflogs came about
quite a bit after that.
Maybe I'm missing something, but aren't unsynchronized clocks a common
thing in personal computing? Even maybe less common, but noticably
frequent, the clocks with the date set way back in the past (by malice
or accident)?