I lived and worked in Frankfurt for awhile (I'm American). My experience was different. Though I was fluent in German and worked for a company where German was the language of day to day work, I found very few Germans that didnt speak English (Those that had grown up in the former East Germany were the exception - this was 15 years ago when the fall of the Wall was more recent). I met Americans that had lived there for four or five years working at some of the international companies there that had never learned German. It did not seem to be an impediment.

I think it was meant sarcastically.

You can survive with no German knowledge if your coworkers target group predominantly speaks English. This is not a given, though.