Resistance and PVP

Why do you keep the resistance penalty from the difficulty you qued from ?

this applies to merciless act 3, you keep the resistance penalty which originally is meant to make you weaker vs monster's you encounter but for high lvl pvp it seems to give an advantage to caster's, as well as forcing player's to use aura's to negate the penalty.

why isn't the resistance penalty removed at least for the duration you are in pvp for ?
the cap on resistance could perhaps be lowered to 50% instead of 75% while in the arena just to ensure that caster's are not getting too weakened by the penalty removal.

it's -60 because the resistance mods on higher lvl items are also higher compared to low levels.

edit:

moving cap to 50% would make caster even more powerful..