May I congratulate you on a balanced reply to the letter headed "Invisible touch" from DH. It is always easy to blame the other guy. Road safety could be much improved if we all understood a little more about the other person's situation.

You are completely right about the "Blind spot" on HGVs, particularly with a left-hand drive vehicle driving on the left had side of the road. The same is true of course with right-hand drive vehicles driving on the right hand side of the road, as with British trucks on the Continent, of which I have many years experience. It is also worthy of note that in most cases the off side mirror is flat, whereas the near side mirror is convex making it more difficult to judge the distance and rate of approach of the overtaking vehicle.

There is however, another situation where an overtaking vehicle can be "invisible" to a truck driver. In wet conditions, if the overtaking vehicle is showing only sidelights or no lights at all, it can be impossible to see that vehicle. The reason for this is that the truck driver is looking through a rain-spattered window at a rain-spattered mirror that is reflecting a view of thick spray. This problem affects all trucks not just those being driven "on the wrong side of the road".