In the past we said this:
It is not claimed that the explanations in this publication are infallible. (Revelation Climax--p. 9)
Those who make up the one true Christian organization today do not have angelic revelations or divine inspiration. (Kingdom Proclaimers--p.708)
Although the slave class is defined as "faithful and discreet," Jesus did not say that it would be infallible. This group of faithful anointed brothers still consists of imperfect Christians. Even with the best of intentions, they can be mistaken, as such men sometimes were in the first century. (WT December 1, 2002--p. 17)
Looking at the recent paragraph some more I think OnTheWayOut is right. They stop short of saying they are directed by the Holy Spirit, but rather that the Holy Spirit "helps" them. Still, though, this gives the impression that all new understandings are a result of the help of the Holy Spirit.