Weird AI knockoff glitch

[AlexJonesRag 0]

While fighting the chess gym Gallade would one shot my Vulpix with knock off so i took the item off. This is where the glitch begins; if my OTHER pokemon in the field had an item equipped  Gallade would use a different move to guarantee a one shot kill on the Vulpix but when I took the item off the other pokemon it would go back to using knock off on the vulpix, despite it not guaranteeing a kill. I first brushed this off as shitty AI but the Gallade would correct its self the next battle going back to using the other move to one shot the Vulpix unless i put the item on and back off again on the other Pokemon.

[Saijo 12]

I noticed something similar while battling the trainers in the grandhall.

Everytime I done something different than before the AI reacts different too, even missing the chance to one shot my mons.