If you think things are bad now, just wait until they have re-re-re-built (is that enough re's?) the bridge footings at the dyke and open the stretch between Crowland and the A47...that stretch is going to be deadly with that long straight followed by the gentle blind bend as you approach Crowland!
Anybody who has lived or travelled around here knows that the road should have been dualled but, it is another case of money over safety. Just look at the staggered junctions at the old radar corner and the back road to Thorney....they really must have been taken straight from the Mickey Mouse book of road designs.
I don't know that the road as is can be made any safer without average speed cameras along the whole road (Gatso's won't work). It's the drivers that need to be changed rather than the road. The only (draconian) option I can think of would be to build great big concrete barriers down the center of the road (like the A47 Paston parkway) to 100% prevent any overtaking but, that would be a real pain if you got stuck behind a farm vehicle that could only do 10 or 20 mph.