Chugalug, Like you I had the pleasure of a similar visit and briefing. I flew BEA/BA S1-11s at the same time. We may even have met in the pub more or less opposite the Ambassador Hotel. One point which was made was the reluctance to allow any Germans into the building in case they took the opportunity to try to create a "shrine" which could have upset the delicate relations the Western Powers had with the Russians.
Happy days !