Offsiding and straightlining - cut from 'Tailgating' thread

[Gareth]

On the specific point of centre markings these are applied to reflect the increased risk of conflict where there is sufficient room to use them. The purpose of the road markings is to segregate traffic.

When a road is wide enough for opposing flows of traffic to pass, what factors relating to risk of conflict do you think are taken into account in assessing whether to omit a centre line?

The only factor mentioned in TSM paragraph 4.6 is the width of the road. How do you think "this road is less than 5.5m wide" supports a conclusion of "the risk of conflict on this road is sufficiently low that a centre line is not needed"?

I think you are both arguing about this from the wrong point of view. When the carriageway is wide enough for vehicles in each direction to pass without conflict and without slowing down, abnormally wide loads excepted, a centre-line is painted.

Traffic is not segregated. Drivers know that traffic is not segregated and can expect to find oncoming traffic in the shared space.

when there is room for me and the oncoming traffic to pass, when we meet each other I expect to find the oncoming traffic on its side of the road not mine, so that we can pass rather than collide. I do not change that expectation when the centre line is omitted. Do you think I should?

When the centre-line is omitted I think it is far more likely that drivers of opposing vehicles will need to accommodate one another, either by both slowing so they may pass in safety, or by one almost stopping so the other can pass at close to their current speed, or by one making use of a passing place, or by both moving partially off the carriageway.

What might be helpful at this juncture is suggestions of specific criteria that people look to satisfy when off-siding rather than the bland and unhelpful "if it's safe"

This might be repeating earlier comments in the thread but ... I look to avoid off-siding when there are blind or otherwise openings on the off-side from which it is reasonably possible to expect a road user to emerge, I require forward vision to indicate there will be no conflicting opposing vehicles for the duration of the off-siding and that the off-siding is unlikely to distress an opposing driver, and that my actions won't come into conflict with a following driver.

[GJD]

On the specific point of centre markings these are applied to reflect the increased risk of conflict where there is sufficient room to use them. The purpose of the road markings is to segregate traffic.

When a road is wide enough for opposing flows of traffic to pass, what factors relating to risk of conflict do you think are taken into account in assessing whether to omit a centre line?

The only factor mentioned in TSM paragraph 4.6 is the width of the road. How do you think "this road is less than 5.5m wide" supports a conclusion of "the risk of conflict on this road is sufficiently low that a centre line is not needed"?

I think you are both arguing about this from the wrong point of view. When the carriageway is wide enough for vehicles in each direction to pass without conflict and without slowing down, abnormally wide loads excepted, a centre-line is painted.

Isn't that the whole point? A centre line is often painted on such roads, but not always. RoSPA's view seems to be that whether it is ever acceptable for me to position across the centre of such a road depends on whether a centre line has been painted or not.

I like your answer to MGF's question about criteria for offsiding. I find RoSPA's rule inconsistent because, on the sort of roads we are talking about, I don't believe there is a correlation between the absence of a centre line and inherent characteristics of that particular road that make the sort of criteria you mention more likely to be met. I have not noticed such a correlation myself and and I've not heard anything from RoSPA, TSM or MGF to suggest it exists.

When the centre-line is omitted I think it is far more likely that drivers of opposing vehicles will need to accommodate one another, either by both slowing so they may pass in safety, or by one almost stopping so the other can pass at close to their current speed, or by one making use of a passing place, or by both moving partially off the carriageway.

That's starting to move outside the scope of the contentious rule though, which is about when "some movement over the centre of the road may be acceptable." If we are discussing when some movement over the centre may (and therefore may not) be acceptable, we are talking about roads wide enough that, if you choose, you can avoid crossing the centre. By definition that's not the case if passing oncoming vehicles requires things like passing places or moving off the road.

[postlover]

From the previous training, the delegates commented that they had been left with feelings of "what did he hope to achieve training-wise with us by driving so scarily?" and "I won't be doing that myself, I'll stick to my normal driving lines".

[Astraist]

I admit I did not read the whole thread (it is quite long...) but I did look through it and I think that presenting my view on offsiding and road positioning for bends might serve as some beneficial input.

On the approach to any bend (both left and right), I would position myself to the outside of the bend within the confines of my lane. I start turning smoothly on the outside and turn to "clip" the inside (again, within the confines of my own lane) only once a get a good view ahead and through the bend. I than run wide back to outside before repositioning for the straight or following bend.

If the bend has an open view throughout and no hazards that require me to position differently, I would obviously try to "clip" the inside of the bend at the geometric center of the bend. Again, within the confines on my own lane. If there is no traffic around me (in any direction) and given that the law permits it, I would offside (on left and right handers) and utilize the entire width of the road at entry, apex AND exit, even if that means running back wide into the offside on the exit before returning to my lane.

I stress that no traffic should be present. This is important to avoid sending a wrong message to other drivers who might misinterpret the maneuver or try to imitate it even when conditions not allow. Also, if there is a following driver, conflict might arise should you need to slow down or if the other driver accelerates into your road position in the nearside or tries to overtake you as you offside.

I usually manage to enter the corner smoothly and gradually, although rarely limited view dictates that steering towards the inside of the bend is left for so late that steering might be done a tad more rapidly than desired. Also, if the surface in some part of the bend is slippery or has off-camber, I would rather than a tighter, jerkier line (as long as there is still sufficient view) that puts the car, or at least the outside tyres, on the grippiest surface possible or allows to pass through a danger zone with straight steering.

In my view, using the entire width of the lane is better than keeping to a tighter line that might put you out of the conflict zone with oncoming traffic, but also gives you poor view towards that traffic to judge whether they might swerve and increase that conflict zone into your side of the road...