Cadillac 2007 DTS Owner's Manual page 184

Highway Exit Ramps
CAUTION:
{
Adaptive Cruise Control may lose track of
the vehicle ahead and accelerate up to your
set speed while entering or on highway exit
ramps. You could be startled by this
acceleration and even lose control of the
vehicle. Disengage Adaptive Cruise
Control before entering a highway exit
ramp. Do not use Adaptive Cruise Control
while entering or on exit ramps.
184
Other Vehicle Lane Changes
If another vehicle enters the same lane as you,
Adaptive Cruise Control will not detect the vehicle
until it is completely in the lane. Be ready to
take action and apply the brakes yourself.