In his book "In Search of Christian Freedom" [pgs 118-121] Ray Franz explores this very problem. In the April 15 1987 WT pg 12, the rationale for altering the baptismal questions was stated as a need to "simplify" matters with respect to the baptism procedure. "Simplify"? what could be simpler than the questions hitherto in use? How could you simplify a matter that was already simple enough even for a moron like me to understand and I took the plunge in ' 57.
The point was that in that WT article, the writers did not mention who the matter was simplified for, and there, my dear Brutus, is the rub. It was'nt simplified for the likes of me and thee, oh no, the WT had a more sinister agenda in mind.
As has been mentioned above, the WTS faced an increasing number of legal suits brought against them by disgruntled former members. They won some of these cases but lost a lot more. Something had to be done to reverse this adverse trend. Enter the Legal Eagles.
The legal brains behind the WTS, probably paid a lot of dough to come up with a solution, found a loophole they could exploit. The US Supreme Court defined the parameters from which a religion had the right to exercise its authority over its adherents. It said that every religion had the "right to create tribunals for the enacting of decisions concerning controversial questions" and that this religious function acted as an "ecclesiastical government for all individual members within the general association" and their adherence connoted an "implied consent to this government"
If, on entering this association, the convert was forced to acknowledge this "implied consent" then any future act of dissent could be viewed as rebellion against a "government" The religion then had the right to dispose of these ones just as any secular government dealt with traitors who had taken a pledge of alliegance to that government. The baptismal questions, since they did not make any reference to any religious authority left the matter open for a dissenter to voice an opposing opinion.
So, now, like a pledge of allegiance to an authority, that is subscribed to as being binding as an oath, the revised baptismal questions make it clear to the new convert that he vows allegiance, not just incidently to jehover and jezzzuz, but to the ORGANISATION. If he sues, or threatens to, the WTS attorneys mail the malefactor a bulky package in the form of a legal brief wherin they cite the above Supreme Court quote, which permits the WTS to act as a "government" and "ecclesiastical court" They then remind the potential dissenter of his "oath" in baptism. So rather than face a potentially damaging court procedure, they invite the person to formally disassociate themselves.
This has indeed stanched the hemorrhage of legal defeats and certaintly "simplified" matters for the legal dept !!!
Cheers