1914 has been so much in the background for so long, it has not really been pushed as an overt doctrine for decades, the acolytes just accept it because it is spoken of as a proven, unquestionably true thing, without going into how it is arrived at.
The average JW today could not explain the doctrine in a way that was understandable, or even vaguely believable, becuase it is not stressed at meetings or conventions, just mentioned in passing.
It certianly is not "preached" to the public, I bet it never even gets a passing mention in DtoD work, the closest may be a reference to how things have changed "since 1914" but that is only referring to the start of WW1 inthe mind of the public, and the JW keeps to himself the bit about jesus sitting on a throne then.
The crafty buggers of Brooklyn have known since the 1960's, when C.O Jonson wrote to them,that the doctrine is total hogwash, and have been quietly burying it ever since.
Their problem is, if there is no 1914, there is no 1919, there is no mandate or authority for the GB today, plus they cannot put the fear of Christ up people because he ain't a comin soon to flame your ass, so they have to keep the whole thing in the background,but cannot totally let it go.
They need fear, as well as the carrot of living forever, to attract new contributors to the scam they call a religion.