Okay, I thought about it and I got it all figured out in a Freddy Franz sort of way.
The pre-1975 "generation" of the leaders saw all the excitement and buzz of building up the organization. It was a real euphoria for the leaders. It came to an end, but many of those guys are still around.
Nobody understood their 1995 explanation of "generation" and they were losing members. They knew they needed a definite end limit to the end of the last days. But jumping right to an explanation that suggested an overlap was something they were not prepared for.
They decided to do it in stages. They broke the 1935 sealing of the anointed (but will now try to insist that the thrust of the work was switched to the other sheep- having their cake and eating it too), they switched the understanding of "generation" to the anointed in general instead of the wicked people in general (a big step toward the current understanding), they prepared the members to expect some major changes and not to question the "slave" if they received odd requests. Right before their goofy new overlap doctrine, they tell members not to copy talks and share them, then they have a typical article where incredible new light is just slipped in. The real thrust of the change will come in talks at assemblies and by Circuit Overseers. They hope to keep this out of youtube- the latest attack on WTComments shows that is true.
I think they remembered that the members will believe what the leaders tell them to believe as long as they cannot put 2 and 2 together. They are attempting to make the work urgent with stupid doctrine and attempting to keep the members from discerning that it is stupid. "Just don't question us." It is a last stand from a bunch of old codgers that want to regain that 1975 excitement before they go away to die. They see Brooklyn being sold off and they just cannot stand it. When this is stretched out to the maximum, they will be dead. But they hope it stops the organization from sinking.
They are not trying to get rid of any old timers. They are trying to retain them, if only them, until they pass away. They want their green handshakes and their rock-star status along with near-worship from the members. If they have to shake out some members that start waking up, they hope the ones that remain are that much more loyal unquestioningly.