Speculation:
If this thing continues to get pushed, whether by true believers or agents provocateurs, then Obama steps forward with a certified copy of his Hawaiian BC that has been witnessed to by Hawaiian State Officials...
Well, it would result in at least a modest loss in credibility by the Republicans if only through implied guilt by association.
Then if further, more legitimate, issues are brought up the administration has a good hill to fight from. It would then be much easier for them to dismiss claims or accusations as just another baseless fishing expedition like that whole BC thing.
This is why we need to be focusing on the release ALL records, the BC being first and foremost.