Even the Watchtower Society acknowledges it was Maria Russell (C.T.Russell's wife) who came up with the peculiar doctrine of the FDS.
Over the years it proved useful.
If you substitute the FDS for the Pope you see how the parallel is quite stunning!
The Pope has the authority to make pronouncements regarding faith and morals and cannot be disputed. So too the FDS.
The big split between the Catholic Church as an institution and Protestantism was over one thing: AUTHORITY.
The Catholic Church reserves the right to guide all christians through the Majesterium of the Pope's authority.
The Protestants say god speaks DIRECTLY to each faithful christian through scripture (Sola Scriptura) or the bible alone.
Maria Russell latched on to this device and made the "understanding" of the FDS identical with Majesterium.
The subsequent application of C.T.Russell was not Maria's idea. Oh no! She thought that, because of the marriage bond she and Pastor Russell were BOTH the FDS!
C.T. Russell quietly adopted the view that HE ALONE was, indeed, the only one through whom Jehovah spoke.
This presented a problem when he died, naturally!
Rutherford let this stand for awhile and distanced himself from that doctrine gradually by applying it to, ostensibly, the entire GROUP of anointed. This was a little closer to Maria's understanding (of more than one). Yet, it wasn't REALLY what Rutherford ended up doing.
Rutherford was the ONLY person who could tell the others what to say and print!
This awkward doctrine has been shaped gradually and makes little sense if you get right down to the nitty gritty of it!
The FDS is a ploy to allow a group of old men in Brooklyn to tell people all over the world what to think and how to act while pretending it comes directly from Jehovah himself through the agency of Jesus (and his established kingdom.)
In reality, all the errors, misunderstandings, false doctrines, wrong-headed predictions indicate these people (FDS) know absolutely nothing about anything!! It has been demonstrated time and again.
But, we aren't allowed to question this authority any more than a good catholic can question the Pope!