I meant the original AI on Medium. QuantumDelta seemed to think that the retail AI fighters always chase you with psychotic single-mindedness like on Insane regardless of difficulty. They fly much better on Medium with your new AI than originally. Even on Easy there's a noticeable difference, and not just the constant missile lock tones.
You're confusing "Vanilla" with "Retail".
These AI constructs Fury put together is much closer to "Retail" than Vanilla is, and, if you were to have a scale it would roughly work out like this.
Vanilla <--- Retail ---> Fury's AI.
Despite the best efforts of quite a few of the SCP duders and myself, the Vanilla bugs that strip retail ai of some of it's 'personality' remain, and

show a marked difference in behaviour the higher up the skill/difficulty (general/insane) ladder you go.
The retail AI could still produce and display the behaviour that the SCP AI do, but they would only rarely do it, SCP AI does it 100% of the time, Fury's AI... I've only seen it happen once.