I spent some time in the small town of Germersheim, near Karlsruhe. As an American, and being around mostly Americans, I would hear the name pronounced such that the 'sh' sounds like the 'sh' in 'shall', like 'Germer-Sheim'. It seems to me that the proper pronunciation should likely be Germers-Heim, with the 's' and 'h' pronounced separately.
I think this rule probably also applies to many other compound words and names derived from compound words, like Oberbefehlshaber, Prosselsheim, Geroldshausen, etc.
What is the correct pronunciation?