"Heath Ledger Might Be Dead, but the Heath Ledger Scandal Dept. Is Still Taking Calls."
The gossip-sheet author who wrote that headline wasn't trying to cast doubt on the actor's demise. He was just using a common rhetorical device: granting a point with might or may, before stating the counterpoint in the next clause.
It seems to me that might was added to that first clause not because of any question about whether the clause is true, but rather as a way of signaling doubt about its logical connection to the point made in the second clause. In fact, you could eliminate the modal without really changing the force of the argument: "Heath Ledger is dead, but …"
Some other recent journalistic examples:
Latin might be dead, but it continues to twitch.
[H]is hair might be gone, but not his loopy humor.
The sandbags and floodwaters might be gone, but the paperwork has just begun.
The rain and wild weather that plagued the weekend might be gone, but the delays remain Monday at LaGuardia.
The price of gas might be rising, but that hasn't completely stopped boaters from enjoying life on the water.
The break may be over, but the Padres still appear to be broken.
London may be costly, but it's cheap compared with Moscow and Tokyo.
Their memory may be failing. But people with Alzheimer’s can still sense when someone is talking down to them.
Ernie Banks may be 77, but he hasn't given up on one of his lifelong dreams.
SDCC may be over, but the news continues to roll in.
Given that Ernie Banks is incontestably 77, why write "Ernie Banks may be 77, but he hasn't given up on one of his lifelong dreams", rather than "Ernie Banks is 77, but …"? If the writer were telling us about Ernie's age, rather than using his age as a rhetorical counterpoint for a discussion of his dreams, then "Ernie Banks may be 77" would imply, counterfactually, that there's some doubt about the matter.
Of course, the same rhetorical structure "possible(P) but Q" can also be used when the truth of P is subjective, uncertain or controversial:
Carbon might be recaptured, but cash won't be.
Pickup lines might be out, but flirting is still very in!
This might be true, but Secretary Kopelousos says finding the money to pay for other transportation projects won't be easy.
It might be apocryphal but the story is attaining mythical status just the same.
Their intent might be honorable, but the impact would be devastating.
Your notebook may be old, but that doesn't mean its days are numbered.
Rumors that Jobs is ill may be overblown, but he's seen as so central to Apple's success that investors are jittery.
I may be naïve but I’m going to believe that Favre does want to get this resolved in a way that minimizes the embarrassment to Green Bay.
It may be bravado but former Blairites are warning that if the cabinet does not act before the party conference, there will be a revolt from below.
DIY may be fun, but it's a challenge if you don't know what you're doing.
So what's going on here? I'll leave it to the linguists who work on formal pragmatics to work it out exactly, because my breakfast blogging hour is over. Me, I'm just defending myself against an embarrassing comment.
Yesterday, in discussing the role of dictionaries in determining whether something "is a word", I quoted a sportswriter who used the "possible(P) but Q" rhetorical device as follows:
Granted, "disappreciation" might not be an actual word, but it was what Lito Sheppard came up with to characterize the Eagles' handling of him yesterday, and, syntax aside, his point was clear.
I assumed without discussion (and in fact without thought) that the Les Bowen was taking it for ganted that "disappreciation" isn't a word. But in the comments, DonBoy retorted "Hey, the original author just said that it might not be a word".
DonBoy, you might be right, but I don't think it matters.