I just played a game to test out a new unit and one of the tanks was 'destroyed' by a crew-killed critical. Leaving it 'alive' but out of the game. Princess continued to make it a priority target, thanks to being so easy to hit.
Obviously not a priority fix, but if a vehicle is destroyed by a crew killed critical, it should drop very low on Princess' priority list to shoot at or be ignored entirely.
I can verify this.
Fixed with [r11046].