In my years as a defensive driver trainer there have been many instances of experienced, newly licensed , as well as learner drivers that have needed 1 on 1 in car instruction on the art of braking to a controlled stop in a simulated emergency situation .
One case springs to mind was when a female became visably upset and it turned out that her mum had told her never to brake too hard as she would lock the wheels and lose control so she would not brake any harder than 7 out of 10 (10 being lock up ) when questioned further it turned out that dear old mum had been in 4 rear end crashes as a result of say tailgating,inattention and failing to brake hard enough.
IMO this is a classic example why some parents should not be "teaching"? anyone how to drive.