Wildbill
Member
Two reasons (at least.)
1. Often, the worse accident is caused by cars following those which have an accident! Suddenly stopping to zero is likely to cause additional accidents, often worse ones. (If EAP was driving, it would have probably already been braking ahead of time, so other drivers would be more aware and the additional panic stop is less likely to cause worse accidents.)
2. If EAP is not engaged and you're driving, then you have your foot on the pedals. During the time that the car brakes from 70 to 40 (or whatever) you've certainly moved your foot to the brake and can continue to brake IF THAT'S THE CORRECT ACTION. As the driver, you can choose whether to deflect left or right, or to just continue to to brake. Perhaps the obstacle in front of you has already crossed the road (deer? Cross traffic?) and you can see the road is now clear. If so, you do NOT want to continue to panic brake and cause someone behind to rear-end you or to panic-turn into oncoming traffic and cause an unnecessary fatality.
This is probably the best explanation so far.
Phantom breaking is an imperfection in obstacle detection and imaging processing. It does not explain why full stop is attempted when TACC is engaged but only 30 mph deceleration is attempted when TACC is not engaged.