forging items for 0 gems

[tinkthank]

I'm sorry, I have still not found the time to work this out systematically, but I double checked again. It really is functioning this way for me. I suppose that an Ulm Smith would have an even easier time to get 0-gem forgings done; I was doing this with a Jade Sorc.
I would be grateful if anyone out there who knows more about math and the inner workings of this game could either verify or falsify my findings. I can only tell what I see.
(PS: I am *not* claiming that forge bonuses help with construction rituals as in that other thread.)