Interesting topic, yes we all bend the rules a little when what we are delivering is urgent, eg the part for delivery to the caterham f1 team that are flying out to the singapore GP that same day, court documents etc etc, but when its a tonne of chilled bean sprouts (sorry Mr G, mentioned foods again) "that we need before 5pm" then I will ask the drivers to back it off a bit, 60mph is a happy medium, 50mph on a motorway will upset all our bigger trucking buddies. To be honest I would rather pay a driver an extra hours pay and get him (or her) back safely than burn a load more fuel and put more tax money in the governments coffers.
Work it out - in the "good old days" before big brother was watching us sitting at 80 - 90mph on the motorway was the norm but you only averaged 50mph, weve all done it thrashed down the A1 over taking everything only to arrive at a roundabout to have mr norbert dingle dangle back behind you - the one you passed 20mins ago.
Speaking of fuel... Cant say I have noticed the difference in performance or mpg between the big names, shell and BP etc but I do think that supermarket fuel is inferior (maybe just me)
Just passed a BP serve station on the M6 north bound near the lakes £149.9 per litre! Think i will be that one a wide berth.