My partner and I witnessed a very disturbing situation on the M4. An idiot of a woman driving a Discovery hogged the outside lane doing about 65 to 70mph. As soon as the middle lane became empty the car behind the Discovery switched safely to the middle lane and overtook this stupid and selfish idiot. The idiot in the Discovery reacted with rage and flashed her lights and hooted at everyone that overtook her in the middle lane. Eventually the idiot switched to the middle lane. Later we stopped at Membury services and found a group of people, including the lane hogger, all arguing in a very undignified manner in the car park. The woman screamed that no-one had the right to overtake her in the middle lane. Was she right? And surely this lane hogger is potentially a very dangerous driver. The anger and frustration this type of behaviour causes is beyond belief.