 Re: speeding on avearge speed check!
Its true that if they have no evidence then they cannot do you for it. Saying that as there were 2 scumbags in the car they can back each other up to a degree.
Also most police car's have camera equipment in the car which records speed so if they were following you and it sais they were doing over 100 then you were obviously going over 100 as well.
Im not convinced about them not being able to arrest you if they have a defect on thier car.
Its like when people used to say a policeman/woman can't arrest you if there not wearing there hat but they obvioulsy can do. | 
