I know I'm stupid but how do you get to Derby direct on the rattler without having to trudge into St Pancras ?
Direct from where? Watford? Derby's on the Midland Mainline. You can't get there direct from Watford. You could go via Birmingham and pick up a Cross Country service I guess. Or it's into town and direct from St P.
Easy for me, 10 minutes on the bus . If you're coming from Watford though it's not so easy. As UEA says, no direct train so change at Birmingham new st.