Like most things in life how something is supposed to work is not the way it works in reality. Most of the time it will be obvious little narrow approach lanes that hardly fit cars, or if there is a “speed brake” put in on approach i.e tight bending approach lanes put in on purpose to slow drivers down on approach to junctions usually R/bouts. You will have to straddle these because of the length of your truck cuts these bends.
Some road designs don’t help anyone and even an experienced driver would get caught out and only local knowledge will stop you looking like a ■■■. Example, when I was doing my “lessons” which were quite a novelty for me a trained driving instructor, my LGV instructor Paul asked me to turn right at the R/bout ahead he was giving his instruction well ahead of the large R/bout as it was national speed limit on approach (50).
The road was dual C/way with very wide road lanes on approach and a good bit wider than the cab, the approach was as straight as an airport runway. Ok mirrors, signal, right hand clear, change lane, good distance to go and starts to slow up. Instructor Paul coughs up after seeing how I would approach the situation (normal driving instructor technique) “you’ll need to straddle this on approach”.
Eh! “there’s bags of room around me” I say, “trust me” says he, I did so I checked the left mirror, other traffic well back and I move to the left and straddle the lanes. As we got nearer to the approach not many yards from the r/bout can’t say how many, I was too busy weighing up the traffic situation on “it” .
The final approach had been choked right down and both lanes were narrowed, after I had finished the turn I asked Paul “how the hell would you know to straddle that”. Paul gave me an answer I’ve been hearing and using in driving instructing for many years “local knowledge, you wouldn’t know”.
Paul went on to explain that this was “one of them new roundabouts” they had put three in the area and they narrowed down for no good reason known to him, except to make life difficult for HGV drivers!
So what I learned from this is that I will get caught out on roads I don’t know and all that you can do is wait till it’s safe to take the space if you get the approach wrong. The only problem with this is the good old DSA expect you to know it thats why your instructor shows you all the local pit falls.
The problem with supermarket assessors is they know this too and really should keep you right, if they know a junction requires “local knowledge” but I suppose this is were it comes down to “if your face fits”.