There was obvious collusion.
I went back and edited the transcript to align with the exact video timing of Øbama's interruption ("dog whistle") and Crowley's intervention. Here is the termination of Romney's "Fast and Furious" remarks:
ROMNEY: I’d like to understand who it was that did this, what the idea was behind it, why it led to the violence, thousands of guns going to Mexi- OBAMA: Candy? can drug lords... CROWLEY: Governor, Governor, if I could, the question was about these assault weapons that once were once banned and are no longer banned.
Romney (following the rules) stops speaking and turns away in disgust, and Øbozo (inappropriately) grins like a possum -- because his obedient, overfed, trained attack spaniel has leaped to his rescue -- at his command.
It is blatantly obvious that (right before Romney could mention the DOJ and Holder's citation for Contempt of Congress) Øbama interrupted -- mid-sentence -- with a pre-arranged "dog whistle" to activate Crowley -- and she immediately interrupted with blather about what Romney was already discussing.