Your Cardas/Benz cart is a moving-coil, which means it isn't critical as to load capacitance. 400 ohms resistive loading could be in the higher range for proper response with a low-output MC anyway, but regardless, choice of interconnects won't have any appreciable impact on resistive loading since they've got neglible resistance. If you want to experiment with higher values, you'll have to accomplish it through substitution of loading resistors in the phono preamp, a subject you might want to contact Rowland about, and maybe also Cardas to see what their experience and recommendation is on the loading topic with your cart.