Seriously? If you cant manage at least 40 mph down a perfectly good A road with a limit of 60 mph then, in my opinion, you shouldn't be driving.
Every morning I get stuck behind at least one person who crawls along at 35mph. Invariably they are driving fast expensive cars too!
Dont even get me started on those who drive fast cars slowly whilst wearing hats..... GRRRRRRRRRRRR.
Disclaimer - it is a perfectly good road, 60 is a perfectly sensible speed, conditions permitting.