Viva la Viva nailed it:
Agreed.
I also agree that this is definitely not to help JWs explain 1914 to others, it's to shut down any doubts that are coming up due to the fact that 100 years have gone by and not one damn thing has happened. if someone at the door asks about 1914, there's no way that they're a potential bible study...they're asking because they know a thing or two about JWs and they're trying to sow seeds of doubt. That's why the 1914 stuff is always at the very end of their indoctrination manual - for them to have any chance of convincing someone of it, they have to wait until they're already deeply invested.
Also, just because they're doing this big 1914 shebang right now, doesn't mean that they're not planning on scrapping it eventually. Right now they're doing damage control and buying time. Afterall, they can't be seen as having capitulated to the passage of time by changing/abandoning 1914 on the 100 year aniversary. Or maybe they just don't quite have the votes to change it yet. Personally I'm about 50/50 on whether they change 1914 before 2034 or a few years after. They do love to set dates, and the current GB is far enough removed from 1975 that they may well believe the lies they tell about what happened then (that some witness privately speculated that 1975 would be the end but the WTS never promoted the date). If they believe the lie that they've been forced to tell for years, then they'll probably see 2034 as valid because they're predicting it, not "some witnesses." 2034 is a long ways off, though, so I don't expect them to start pushing it for another 10-12 years. In that time a lot of things (including 1914) could change.