Could anybody please provide me with some carity here.

Let's say i'm a rank 1 gladiator and i've equipped a sword with an optimal rank of 7.

Do I get reduced stats to coincide with my current rank?

Does the sword degrade quicker than it would if I was rank 7?

Ultimatley, what is the benefit of being the optimal rank (or higher) as opposed to equipping an item a few ranks below?

Thanks for the assistance or apologies if i've just beaten a dead horse.