Strange evasion tactics - Constant Rolling

[He111]

I've noticed when a AI plane sees an enemy on their 6, it's usual evasion tactic is to roll .. and roll .. and roll some more .. ??? Even for defiants, which should be banking left or right. (see it in this video)

Another annoying thing is, in the mission builder, I set 3 defiants to go 'attack bombers' then flew a He111 right past them. They decided to do a long banking turn instead and virtually ignored the bomber .. ??? (see video)

Is there any way to set tactics for AI aircraft ??