Does anyone else find Letterman's story that he found the package (from CBS producer Robert Haldeman) in the back seat of his car, and opened it, implausible?

Letterman has already been troubled by a stalker who trespassed on his property repeatedly, so I assume that security at his home is of the highest quality now. So how would Haldeman have bypassed that security and entered the property and the car... unless, perhaps, Haldeman's former girlfriend (Stephanie Birkitt, who is also supposed to be one of Letterman's staffers with whom he had sex) had keys and/or security codes that Haldeman somehow obtained (with or without Birkitt's cooperation)?

Even if Haldeman had managed to get onto Letterman's property and into his car to leave a package, why would Letterman have opened it instead of calling the local bomb squad????? Either Letterman is royally stupid, or he's lying.

It has been suggested in the media that the Letterman story appeared when it did in order to increase Letterman's TV ratings and draw viewers away from Jay Leno's new prime-time program. I'm beginning to wonder if it's all a fabrication by Letterman and his staff. If it is, it's at the expense of the reputations of a lot of people (Haldeman and Birkitt among them).