Lets not get too far afield here, I assume that bag is talking about not only exhaust contrail, but wingtip contrail which occurs in hard manuvering.
(A bunch of you armchair aeronautical engineers are about to come in here and say 'No kurt you're talking about Vorticies'.... Don't bother, because I'm telling you that wingtip vorticies are present on any wing that is generating lift at any time... I'm talking about visible condensation due to extreme low pressure above the wingtip in manuvering flight).
Wingtip contrail would not simply be eye candy, this would be a great 'tell tale' on how hard your opponent is pushing... AND it uses graphics that are already in the game (airshow smoke... except white only)...
The idea being that at lower altitudes, the contrail comes on at g-loads of say 4 or 5.
This was/is not an uncommon phenomenon in hard manuvering aircraft.