Operational Tempo.
Left jab, left hook, right cross.
The news about the gay Romney staffer being thrown under the bus was on 1 May. Biden recorded his interview on 4 May, but it was broadcast on 6 May. Obama made his declarations on gay marriage on 9 May. Three working days for each news cycle to release, digest, and let the chattering classes make their comments.
What better way to contrast Romney and Obama's treatment of the same issue?