It's not a discrepancy.There is a discrepancy between 7671 and the codes observed by manufacturers and the ESC, which suggests 0.75 conductors of an appliance lead can be protected by a 13A fuse (up to 700W 3A, over 700W, 13A).
I have long battled with this with my bosses, but I argued I worked to 7671, not the other code.
Presumably the appliance cannot overload the cable and 0.75 is adequate for the fault current.