Skeptical is a nice euphimism. It is always the shooter's responsibilty to make certain the line of fire is clear.
I will go out on a limb here and presume Whittington has done quite a bit of hunting. I mean, only the upper crust ever make it out on Katie Armstrong's patch of heaven, dontcha think? All these boys have probably been shooting their great grandad's Franchi since before they were old enough to bully the hired help. To think Whittington was doing something so completely and totally asinine or unexpected that it relieves Cheney of responsiblity seems far fetched.
Sure, accidents happen. But Dick's --cough, cough--"straight shooter" image is going to suffer unless he stands up and takes responsibility.
Update: Better late than never, Cheney takes responsibility during interview with Fox News' Britt Hume on 2/15/06 . I'm curious to hear from the many condescending Bush/Cheney Monarchists who knew it was Whittington's fault.