>That's cos you view yourself as a roughty-tufty ex-squaddie, used to driving big army trucks through forests, while talking on the walkie-talkie, avoiding artillery, holding a prisoner at gun-point and rolling a cig with your free hand. But not all the population can be so relied upon. I know a guy who can't monitor the output of a xerox and answer a yes-no question at the same time.

My math teacher would say that only Napoleon was capable of doing three things at the same time (*); the rest of us should better do no more than two.

Driving is an art of doing multiple things almost simultaneously. Just think about it - there are a dozen things you need to see and understand (road around you, road far ahead, vehicles and other moving objects around you, their likely trajectories and speeds; road signs and their meanings; your dashboard; where do you really want to go and should you switch lanes), sounds you have to understand and decide whether they need reaction (any funny sounds from your car; anyone honking - who, to whom, why; any special vehicle sounds, like sirens; did your co-pilot just call you a moron?), things to do (shift, pedals, levers, switches, steering, he's an idiot and you need to think what to say)... so adding one more intensive act is not really easy and can cause any of the above to slip.

If it maybe doesn't merit a separate law, it should still be reckless driving, if one causes as much as a dent. In case there's a Napoleon out there who can do it without effort, whom we shouldn't stifle.

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(*) for some reason, these three things seem to be "run, pee and read newspapers", but almost everybody gets confused there and it turns out into "run, read and pee newspapers". Luckily though, almost nobody ever notices the error.