What, then, was Felix Yussupov's motivation for concocting such an elaborate murder story -- outright drama for drama's sake, or was he covering for someone?
I have several theories. There is proof that his mother, Zenaida, and her best friend Ella, (Alix's sister and Dmitri's aunt who practically raised him) were very much against Rasputin and had both been disowned by Alix for telling her to get rid of him. Also, Zenaida's cousin Anna Rodzianko was the wife of Michael Rodzianko (sp) who was the president of the Duma and also very anti Rasputin. So it looks to me there was a conspiracy behind the scenes as early as 1913. This is why Felix, and Dmitri, were involved.
Why did he take the blame? My guess is that he wanted the 'glory' while the real shooter, Dmitri or Raynor, did not. Also, since he never served in the military (other than that military school just for the source of a uniform as I mentioned before) I think he felt this was his duty to his country. Later on, everyone else realized it was a mistake, but he was still bragging. It was his claim to fame, especially after he lost his fortune.
Thanks Richard for coming back and posting more info!