I once did a training trip as a passenger in a traffic car...Volvo. Part of our ops room training for familiarisation with what it was like at the sharp end and be able to communicate the officers needs better. Instructor drove with an ongoing commentary. We got up to 140 on the A40 to experience the public road high speed thought needed. Nothing more such as T-Pac or Stinger deployment. We did some town higher speed routes too. All with lights and sirens.
Chatting with the instructors was a huge plus as it highlighted techniques for observation. We had a couple of bikes join in at one point to show how they could set up roundabout, junction clearance to let us through. Part of the demo included use of systems to get car details.
Officers have to qualify for various car driving, no pursuit unless trained etc..
If we were borrowing a pool car to go somewhere ( I did once) we had to be assessed by an instructor beforehand. He pointed out some minor improvements I could make but nothing untoward. Phew!