Armour reduction on hit support gem/weapon property/skill effect.

I'm a bit surprised that armour reduction isn't already in the game, it's a common attribute in ARPGs. I was thinking about how high amounts of low damage physical hits are overall worse due to the way armour works and remembered back to my berserker in torchlight 2, who had a lot of passives and item stats that removed enemy armour on hit.

I'm suggesting a support gem that would reduce enemy armour but at the same time I think it would be interesting to have as a random weapon stat or even an innate part of high attack speed attacks like Cyclone.

As for scaling, I think it'd be best if armour reductions have a duration, so when listed on an item/skill it would appear as "Reduce enemy armour by X for X seconds". Like with the recent LGOH change, damage effectiveness could lower the duration by the %. Each hit would start its own effect and not refresh any others, so a lot of high attack speed armour reducing hits would lower enemy armour by a large amount but only for a short amount of time so the effect would wear off after a volley of attacks. Slow attack speed but high damage effectiveness hits would stack for longer but not reduce as much.

Basically this is to make high attack speed melee attacks comparable to the high damage armour penetrating attacks that are best for maximising DPS. It would at the same time add another property for melee users of any playstyle to make use of. So why not?