It might be useful.
Why have any ratio though? If 6000 stone takes 6000 seconds, 1 second each, then 1 bundle of 6000 stone should take 6000 seconds, at which point it drops all 6000 material into the forge. The benefit would be in being able to load MORE resources than fit into a stack into your forge at once...and that's it.
For people that use 1 or maybe 2 forges for solo play and small scale building and crafting, they'd probably stick to the individual pieces, since the materials would be melted into the forge gradually, letting them queue up stuff to craft in the forge right away.
For the people running giant multiplayer games, or over-the-top industrialists who have forges churning away on a huge scale nonstop, the bundle would still give resources at the same rate, but you'd have to wait until the end of each bundle. On the plus side, you wouldn't have to manage constantly topping off your forge with resources....it'd be a "load and forge" situation, with the cost being backloaded resources
