I left the masters on and flattened the battery at Deauville in a PA28. One of the mechanics took it out and put it on charge. He told me to come back in a few hours so I spent a pleasant day in Honnfleur. On my return the mechanic put the battery back in and refused to take any money - even for a drink.
The moral is; if you are going to do something stupid, do it at Deauville. Honnfleur is well worth a visit by the way.