As funny as this is, I imagine Vader would simply force grip The Doctors neck afterwards. A sonic screwdriver is no match for the power of the Dark Side!!
Awwww.... from David Tennant's Video Diaries (HOW DID THEY NOT GET MARRIED IN REAL LIFE?!!?) ^I reiterate the last pinner's question!! I have often wondered the same thing myself. I would so totally ship them... but then I remember that he's married.