The automatic transmission in these cars is designed to be smarter than your average bear as it takes various inputs from the cruise control, inertial sensors, load and rpm status to figure out what the car is actually doing before adjusting it's shift points.

If you are climbing a slight grade in cruise mode, you will notice that the Crossfire does NOT jump between gears on a long steady grade, even if it's on the edge of a gear. The system is intelligent enough to know it should simply hold that gear.

Also, when descending a grade, it will downshift in order to trans-brake, just like an intelligent driver would do in a manual transmission.

These cars have an ENORMOUS amount of high technology in them. Don't be too surprised that the car is thinking better than you do on occasion.