maneuver based AI can be too predictable if it doesn't change quickly enough. 2 seconds into a maneuver, I know what the enemy is doing, and can position myself for the kill. Real pilots don't assess the situation, select a maneuver, then blindly execute it, then reassess the situation. The situation is reassessed continuously, and maneuvers are adjusted appropriately on a continual basis. For this reason, i prefer a more dynamic AI that works at a lower level, simply dictating turn and accel rates, vs entire maneuvers. a layered strategy is then applied: 1. collision avoidance. 2. evasive maneuvers. 3. maneuver for kill. The ai then degenerates to simple rules like "badguy left, turn left", "badguy above, climb", etc. maneuvers can then be layered on top of this: "badguy behind and above, do Immelmann". this would kick off a "script" that would do a half loop followed by a half roll. but you don't just execute the "script". each "frame" you assess the situation. if you should continue the Immelmann, you continue running the "script", if not, you stop the Immelmann and do something else. the situation should be re-assessed, and the maneuver changed if needed, at least once per second to be sufficiently responsive. And an experienced pilot will notice that one second lag in decision making on the part of the AI. A good pilot will take advantage of it to get a leg up on the AI. A really good pilot will be disgusted by it as being too slow to react to the player in a timely manner. A full one second head start on your opponent is WAY too much of an advantage for a really good pilot.

You're imposing gameplay components onto a broad idea. Take for example, a very fast paced flight game, where an immelmann can be completed in just 1/2 a second.

That's enough time for you to recognize the move, and bein reaction, but not line up your sights.

On the opposite spectrum, an AI that doesn't have a cheat sheet of effective moves is going to have situations where it makes very stupid choices.