I don't think it was a question of giving up control. I would characterize it as a power struggle with DM eventually winning, but where the Brokers where temporarily on top.
It was very strange in that there was never any explanation as what happened to the Brokers or why they resigned, but it was all official because DM said so.
The whole Loyal Officer thing was originally announced in January 86 a few days after LRH died. The Brokers where on stage with DM and the three of them laid out the new ranks and who was "top boss". In order it was 1) Pat Broker, LO; 2) Annie Broker, LO; 3)DM (just a lowly) Capt.
IAS Administrations and Author Services, Inc has the about the same status as RTC personnel. IASA staff and ASI Reps dine with RTC, get the same privileges (the IAS reges touring with the WIS? Exhibition were driving BMWs and stayed in five star hotels etc.)
IASA is just a membership organization, in fact they are the personal money collecting army of COB. He is running ED IASA directly AFAIK.
Church of Scientology International is just a legal facade. Does not really affect internal org board and seniority.
Finance and Estates Network was missed from the network list.
CMO degenerated into getting COB orders complied to at all costs.