Not sure how you can have a constant fuel rate of at least 90kgh.
From what I got out of the article, they're looking for a constant rate under full throttle, ie when teams may or may not have been getting a small kick out of some trick plumbing around the sensor. If it stays steady it means there's no period of over/underpumping which may or may not give the alleged advantage.
Sounds sort of like the opposite of the engine over/underrun that kept the throttle partially open during the blown diffuser years; only this is temporarily holding back that fuel for a moment for a little burst instead of continuing to force it through abnormally which temporarily lowered torque for some extra grip coming out of corners. RBR had this down to an art form.
Disclaimer: Tales from my ass. I'm no engineer. I'd still prefer they axe fuel rates entirely during the actual races and let the teams figure out how to best use the 100kg.