Can anyone confirm that Hamburg would be 4x daily? Are RYR really jumping in with a daily offering on an established market like that?
By the way LAXLHR, saying that 4x daily to HAM is the same as Frankfurt overlooks the fact that Hamburg is actually a much bigger and more interesting city than Frankfurt. You could say that the 4x daily to FRA is really a 4x daily to Lufthansaland....also a reason why there is no-one else on that route and why previous attempts have failed.
Also - I agree that Stuttgart should be safe...Nurmberg is a loooong way away. Stuttgart's main competitor is from those who prefer to fly to FRA and get the train from there direct to Stuttgart city centre....and it's survived so far despite that.