Trouble is you can't take that nap on motorway hard shoulders - you have to be 'off road' or a service station - not always convenient when your tiredness hits you on the M25
Chocs, drinks, cold air, loud music and windows open - only helps me for a about 5 mins - still think the "awake" companion is the best option.
Most dancing travelling companions have asked for a lift and therefore, I think it is selfish, and bad manners for them to sleep on a long journey home (unless you say it is OK of course)
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