So, you know... there's that. Not that it's ever hindered her, mind (although a scene involving the TARDIS flooding once had to be cut due to Karen's lack of water experience), and now that she's living it up in LA, it's probably not much of an issue there either. It helps that actors get driven everywhere, of course. How the other half live, eh?
Dan Butler is the Doctor Who Editor at WhatCulture.com. When he isn't writing his own articles or editing other people's, he can be found trawling the internet for gifs of Steven Moffat laughing. Contact him via dan.butler@whatculture.co.uk.