It's manageable, of course, if the relationships are disclosed in advance and voluntarily. In this case that wasn't done, which means it's safe to assume the worst. It was a big deal when George Will didn't disclose his wife worked for Scott Walker.
With full disclosure, the viewer can make an informed judgment.
And I maintain if indeed that disclosure was a requirement, it should have been followed... but at this point, that's unknown. The fact that Brooke made her connection to Rubio's campaign public very early on blunts the whole notion that there was an intent to "hide" something.
And.. the idea that Rubio can sharply respond to questions at debates is attributable to somehow having been "fed" the questions is laughable. He performs equally well on the debate stage at other venues (CNN's, for instance). I would find it rather difficult to believe Candy Crowley gave Rubio such an advantage.
Conspiracy theories are fun, because they're participative... everyone gets to play. But this is much ado about nothing.