Just a dozen.
I did think (after posting) that in a way my answer was a kind of 'blocking answer' in that it didn't really answer your question. I'd define a blocking answer as one which is specially formulated not to answer a question ~ methods may vary from politician to politician and depending on circumstances. Some politicos when being interviewed have an agenda, i.e. stuff they have come on the tv to say, and they will just go right ahead and damn well say it, regardless of any questions that may be posed to them. At other times you'll hear them patronizing the arses off the interviewers with such responses as, "With all due respect, Jeremy, that is not a sensible question to be asking at this time ~ what you should be asking ..." Etc. etc. etc. ad [literally] nauseam.