Thread:RedstoneDemigod/@comment-27959912-20170511091255/@comment-26547082-20170511095027

I believe the two separate categories are necessary as they indicate to readers whether the block/item can be smelted, or is already a smelted item. Having a single category simply called smelting wouldn't differentiate between the two states of the item, and those users who find the separation useful wouldn't be able to identify the different items when going through the category.