Nigel
Having spent 6 years stationed in Germany and having towed a cararvan for most of my leisure time there please be aware of a few different 'rules of the road' especially on some Autobahns. There are on many of them strict rules on what can and cannot overtake whilst on them, this applies to trucks, buses and caravans. You may find yourself stuck in the inside lane behind a truck and if you attempt to overtake believe me they will let you know! I made that mistake on the Autobahn heading down towards Switzerland - trucks, buses all flashing lights and horns - most embarrasing! With regard to A roads they tend to stick to the speed limits rigidly and the existence of the 'Boy Racer' element seems to be discouraged - they all head for the Autobahns. As the speed limit on A class roads is 100kph you should not find yourself being held up to much. It would also be a good idea to check the highway code for the continent as there are some very important differences with regards to 'Priority' roads and giving way at cycle crossings. Where are you going when you are there?