From bombers barrel rolls I can guess they made a model of a generic human pilot which flies every aircraft in the same way. This pilot has a very wide range of skill levels from rookie up to "the best ace in history of aircombat".
Problem comes when a mission maker does not adjust skills levels to the mission needs and aircraft types as explained here
http://www.bobgamehub.blogspot.com/2...-of-dover.html
If all 8 skills of all AI in a mission are set to "the best ace in history of aircombat" they fly like those aces of cause.
The devs did not have a dedicated mission maker when they released CloD. Now they hired B6 to make missions for BoM. I hope he does the job better. For CloD it is easy to adjust AI skills in FMB as described in above link or using the AItweak program
http://forum.1cpublishing.eu/showthread.php?t=31573
Feel free to create a new entry in the bugtracker asking to correct AI skills levels in stock missions and campaigns specifically.
QMB missions with corrected skills can be downloaded here
http://forum.1cpublishing.eu/showthread.php?t=31193