Doesn't it work properly? We have the same problem with RENFE.
It works great... fast, accurate, extremely comfortable... I feel like a king when I travel with them!
But there are two reasons I hate it:
1. Way too much expensive! One needs 130 euros for a round ticket Berlin - Hamburg and even 250 euros for a round ticket Berlin - Stuttgart!
I would prefer them to go for a certain middle-ground - less comfort but smaller prices too!
2. The main reason - they hold a complete MONOPOLE on the transport of people in Germany. There are very few buses out there because of that. Buses are, of course, not nearly as comfortable as trains, but are much cheaper - only 20 euros for a round ticket Berlin - Hamburg. And I would like to have that option available also - less comfortable but cheaper.
I have a cousin living near Erfurt. I asked for buses and they told me on the main station: "No buses! Only trains... trains are monopole!"