I don't know about you, but I like having more efficient ways to smelt my ores than the traditional methods. I also bolstered the experience a bit since it's quite a challenge to get to the stage where you're smelting ore blocks with blast furnaces, and since you'd be using this method over an automated furnace anyhow, I thought I'd add a little encouragement to do so.
currently this only works with iron, copper, and gold, and transforms those ore blocks into blocks of the metal. I'm thinking about expanding the idea to extend it to some non-traditional uses, like turning charcoal into a coal block, or zombie flesh into leather. But I go back and forth on those ideas, so let me know what you think.
Also to note, the ores cook for 600 ticks, as opposed to the traditional 200 ticks, and so I've found the ratio of coal to ore block is 6:8, if you're looking for matched perfect cook times and less waste. :) I did it this way as a balancing process against the ease at which this enables resource use: being able to cook 9 pieces of ore with one piece of coal felt too good of a bonus when having less resources to manage was meant to be the main benefit here. So instead you all get an extra third of an ingot per coal and just have to do a little math ahead of time when you calculate your volumes. I felt like increasing complexity was a good way to balance the benefit. This is another one of those things where I ask folks to tell me what they think, as my goal is to make the game more fun, not easier.