I remember some years ago I was setting of on a work trip at 7am Sunday morning, we were travelling down the M6, which was deserted, when we came across this elderly couple idling down the middle lane at about 35mph, my mate started flashing for the driver to move to the slow lane, no chance, his wife was looking out through the back window looking daggers at us, eventually after a few miles he actually moved over, as we drew level this chap shouts there's another lane out there why not uses it, to which I informed him in words of one syllable that HGVs were not allowed in the fast lane
