Since the number gets rounded, this is utterly useless. I haven't encountered any crafts that require more than 2 of an item. The only reason I'd get the upgrade is to see what comes after it :[

I searched for a thread discussing this about a week ago. Glad that I'm not the only one disturbed by this.
I was expecting crafting costs to diminish to 0.9 / 1.8 / 2.7 alloys following the upgrade. The game can be made to handle values with decimal points for alloys and crafted items. No need to show the decimals in the inventory, we're used to have rounded values, and above 1k we lose the sight of the last digit anyway.
A problem might be when someone has 0.8 bars of an alloy, shown as 1 bar, and cannot craft an item requiring 0.9 bars. But we are already familiar with the reason why 1.6M armies are insufficient to conquer a territory requiring 1.59M armies, so we'll learn to live with this as well.

I think it just has to do with how the levels are generated and the generation not understanding that the tech won't get use. I think the first time i got use from it was Breaking Green, you will have to get it though for the buy all techs achievement though.