If you want to test the German wine savvy of your knowledgeable friends, here's a little experiment you can conduct in the safety of your own living room. Tell them you want them to taste a German rosé, and inform them that it will be off-dry, well over ten years old, and come with a label sporting a coat of arms and cryptic Germanic font. Mention in passing that this bottle will come from the Müller-Catoir winery. 95 per cent of all wine drinkers will at this point have run away screaming, the living daylights scared out of them.
The remaining 5 % will ask for a screwpull without further ado. From then on, listen to those people.