It's being reported that Zardari was the one who'd originally refused to allow an autopsy to be done on wife Benazir's body, on the grounds that it would be an insult to her, a sacrilege, etc. If true, then I'd find such a refusal to be highly suspicious.
Consider that it's also been widely reported that Zardari's marriage to Benazir had been breaking down, and that like many political couples, they were simply staying together for appearance's sake. Zardari, like many Pakistani husbands, might not be willing to play the role of a submissive husband for the end of his days, like Indira's husband Firoz.
What if both Zardari and Musharraf had found common ground in protecting their interests by having Benazir "suddenly removed" from the picture?
Then Zardari gets son Bilawal crowned party head, while Zardari himself gets to be the real power behind the son's throne. Meanwhile, Musharraf benefits by getting the same power-sharing deal with PPP, but minus the presence of the annoying Bhutto woman.
Zardari's refusal to allow an autopsy on his wife would be consistent with such a scenario. Also consistent with such a scenario would be the govt trying to cover up evidence on the circumstances of Bhutto's death. Note the govt's denial of any gunshots on Benazir's body, in contrast to the newly-released video evidence. Also note the immediate hosing down of the crime scene, washing away evidence, rather than preserving it for investigators. Musharraf's govt doesn't seem to be making strenuous efforts to get this crime solved. I'm just wondering why?
Please also remember that the Commando-General is a ruthless adversary. He can be very creative in his tactics when cornered. And you have to admit, he has been feeling pretty cornered lately, with the whole US-brokered electoral arrangement.
Just a little paranoid theorizing from me.