[allan]

This was almost always a five car train, including the baggage car immediately behind the lok. For a short time only, a second baggage car was used at the back of the train. Two additional passenger cars could be added if there was sufficient demand - rarely.

There is more info at
http://en.wikipedia.org/wiki/Rheingold_Express

 

[allan]

We are talking about one extremely luxurious train, running through a country boasting astronomical inflation in the middle of the Great Depression (note the capitalisation...).

That said, DRG passenger trains, especially the really fast trains, always seemed to be generously powered. An 01 with four bogie cars, and not matching bogie cars at that, was not unusual.