Okay, armchair speculation it may be, but if someone learns a valuable lesson as a result, it is no longer pointless. That is one of the reasons for high school debates, is it not?

As of 10.35am BST today (March 27th), the BBC News website reports that "Police said no-one has been charged with any offences at this stage.".

In a fatal accident I understand that the driver would be arrested as a formality to avoid any possible tampering with evidence - for his own good as well as in the interests of justice. Had nobody died, maybe they would not have considered it necessary.

The fact that the lorry hit the coach with sufficient force to catapult it as far as it did is indicative either that the driver was not able to stop within the visual distance limit imposed by the fog (he was going too fast for the conditions), or that he had had a 'momentary lapse of concentration'.

Unfortunately there are too many drivers who are quite blasé about fog - they believe their reactions are good enough to cope. Sadly, reactions aren't everything. If you have not sufficient braking distance available, your reactions don't count for much anyway.

Modern vehicles offer so many 'safety features' that some people (subconsciously?) believe they are invincible when behind the wheel.

Of all the perils that face us when driving, fog is probably one over which we have least control. Snowploughs and gritters can minimise the risks of snow and ice, but fog, particularly patchy fog, cannot be reduced - we have to drive within the limits it imposes. Regular use of windscreen wash/wipers is highly recommended.

My own tactic in fog is to drive a safe distance behind the lights of the vehicle in front, working on the simple principle that, because I can see the lights, there isn't another vehicle in the way. Admittedly, there is a flaw in that plan, though - supposing something were to fall off that vehicle?

If there is no vehicle travelling in front, that presents a different set of problems. A good tactic is to use roadside furniture as a guide to how far you can see. Street lighting is helpful (where it is present), but can lull you into a false sense of security.

Speed and fog simply do not mix. End of!