I remember in year before the announcement was made that they had decided to axe the bookstudy citing " reducing midweek travel burden for the brothers" as their reason there was studies in WT or KM or maybe both where the book study was praised as being such a blessing blah blah. Then when it was dumped I thought hmm so that's the change code if they start reminiscing about how wonderful an arrangement is and start going into it's divine inception etc then it could be the "windup music" for that particular arrangement.
I think WT does reveal their intentions before they carry them out and so this statement of infallibity could be laying the groundwork for some future change.
But this is WT we're talking about The Kings of Spin and The Masters of Confusion so.....
Maybe yes, maybe no.