Very true Oblomov, but those statistics showing markedly decreased effectiveness of flu vaccine in those who have been previously vaccinated against other strains are concerning - if true. They suggest something worse than lack of effectiveness. They suggest a blunting of the immune response - along the lines of what allergists are attempting to do with desensitization. That said, I would have to see a lot more data from credible sources.
http://cid.oxfordjournals.org/content/early/2012/03/13/cid.cis307
“Increased risk of non-influenza respiratory virus infections associated with receipt of inactivated influenza vaccine”