Exactly right. I've had a couple of DL friends ask me about the rumor. Their sources seem very suspect, and I think it's mostly a case of 'Hawaiian fever', where they picture themselves on the beach with fruity drink in hand. As others have said, buying the entire airline for a single slot to HND is ridiculous. The Japanese authorities will be opening up HND for more slots in the near future, so what would be the point? The expense involved with a buyout and merger would completely overwhelm any gain for the route, and the ability of Hawaiian to make a profit is based on its being 'Hawaiian', not 'Delta flying to Hawaii'. The brand loyalty, and service that makes HA profitable would go away, and so would any concieveable profits from the merger.
Sure, it may happen, because airline management is human, and just as susceptable to Hawaiian fever as the pilots are. I'm just saying that it wouldn't bring the 'synergies' they love to talk about, and would ruin a very good thing for everyone involved - HA, DL, and the people of Hawaii too.
HAL
SWA bought airtran. Who would have thought that would happen? Consolidation is good for the bank account (managements, investors, wall st). I doubt people will stop flying to Hawaii because of the name on the side of the plane.