What Mark Schmitt said about this. It's astounding that the Clinton campaign has, in essence, wasted an enormous amount of senior staff time on trying to spin reporters and bloggers about superdelegates. The only way they could possibly persuade superdelegates to rally around the Clinton cause would be to start putting some convincing wins together. Having lost 187 primaries and caucuses in a row, at this point that means very solid wins in Texas and Ohio -- not more bluster about Michigan.
UPDATE: See, for example, this sort of bullshit isn't the kind of thing they need to be wasting their time on. Persuade some people to vote for you!
There seem to maybe be too many aides over there who enjoy talking to reporters and want to come up with some interesting debater's points about whether or not there was a campaign in Florida and the metaphysical status of DNC at-large members when they need to be talking to voters.