2. Approaching motorway, starts to turn left to take Eastbound slip road. Realises error. Backs up and does speedy, efficient three point turn (making sure road is clear), continues on over/under motorway to take correct Westbound slip.
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Firstly, regardless of how efficient or otherwise she managed her 3 point turn, it's an illegal manoeuvre.
Secondly, it is incredibly reckless.
Just think about it....
She would have come down the sliproad the wrong way facing oncoming traffic!
Also, realistically on many motorways in the daytime, cars travelling at speed will quickly appear behind you when you're pratting about doing a 3 point turn and driving the wrong direction towards them, even if the road was clear when you first looked. Imagine if it was a speeding lorry hurtling towards you?
If you accidentally exit at the wrong junction, you continue up the slip road and either get back onto the motorway via the same roundabout junction or drive on to the next junction.
Anyone that cannot appreciate how stupidly dangerous that manoeuvre was really shouldn't be driving. I don't care whether they are 18, 50 or 90!
Driving a car is not a right but a privilege that bestows a moral obligation to be considerate of other road users and not put them in mortal danger!