I never heard that before of putting the transmission in park while driving to lossen the stuck overdrive. I thought like you said that the car would lock up and you would be doing a four wheel drift off the road. Or your teeth stuck to the dash? Did the tech mention, or do you know, is there a built in safety to protect the drivetrain against an accidental push of the lever from D to P at speed? I am sure *ss hell not going to find out for myself! When you mentioned it I thought it was the craziest thing I ever heard. But it worked.....unbelievable.