I do not credit the story for initiating the rivalry, only an example of it that set the stage for the two classes' interactions on a competitive level. This is just an image that comes to mind when I read item flare text like "It was the warlocks who taught hunters to blink..." and "oh yes, a fine cloak, but I have a super condensed super-collider on my arm, can your cloak split quarks?" not exact quotes but these all follow the same competitive tones.