What I found interesting is that over the last few years it seems the WTS has worked to separate themselves from the preaching work
In the late '80's there were two talks given at a District Convention outlining the difference between the WT and the GB. The talks covered the probability that the WT (the corporation) would be shut down by "Caesar" and how important it was to note that the GB could not be shut down, they would always be there for Jehovah's people.
It makes sense that they would work to separate the two, i.e., removing GB members from corporate positions.
Is this what you had in mind?