Several points to try to cover, but first it has to be in relation to Ducatti and the terrible way the managed Casey's contract and in effect lost him to the other side.
All the claims of they wanted Rossi to sell more bikes because he has more of a following/is more personable or similar, are in my opinion misinformed. The single biggest way for a company to sell its products is to win races and championships. Look at it in reverse, HRC had Repsol and Pedrosa, from a geographical and population stand point there is no way Casey and Australia can purchase as many products as Dani and Spain can. However HRC threw the kitchen sink at Casey to get him, including hiring Livio Supo 18 months in advance to give them the game plan to attract Casey. They knew the single most important thing they could do to make money (what its all about) was to win races and the title.
Ducatti in turn were flippant about what Casey could do on the bike, they believed that Rossi could replicate it and in turn felt Casey was replaceable. In my opinion I dont think Rossi will be able to, and for all the talk of Rossi developing the bike, I just dont see what is meant by this. Casey has stated several times that Ducatti do not develop their bikes. In his time there what was rolled out for race one was the same bike that they completed the season with. They obviously tried to adjust set ups etc... but they did not introduce new parts, other than perhaps a few minor things. So what they do now will be interesting to watch and see how the 'Develop'. ITs entirley possible that Casey's opinion of what constitutes development is not what Ducatti's is, ie putting a winglet on the front end to stop it from washing out.
Casey has always suggested, even back in the 250's that Lorenzo is the real deal, his title last season was not due to him copying Rossi, he won that on merit and will be around for a good long time. Rossi will come good on the Duke but I cant see him troubling the top 3.
What is the genearl thought of how this season will reflect on the retrospective riders and teams of Casey and Rossi. Clearly its resluts dependant right? If Rossi is quick and wins races the Ducatti are laughing all the way to the bank, if Casey fails and has an average season, multiple crashes and does not show the occasional flash of speed then Honda will assume that Dani was taking the bike to its capacity in the last few seasons and re soildate their support for him.
Alternatively;
If Casey nails it wins lots of races, and lets say not the title, shows his speed and looses out to Lorenzo or Dani, and Rossi struggles all season on the Duke (yes very unlikley) then it in effect suley will taint his image and demonstrate that the Duke really is a terrible bike.
All hypothetical but the point remains, its about winning races, all of this doing x amount of PR and Duke wanted to get rid of Casey because he was over it etc... dont make sense to me. Casey did his share, but he was in the top couple of riders out there. Duke have made the call that Rossi can replicate Caseys results, if they did not believe that they would have made a stronger play to keep Case. I just tend to think they have got it wrong, time will tell.