It works perfectly fine after it has been set up yes.
It stops working perfectly fine once you use it for a while and swapping the molds for other ones.
Also, your test setup doesn’t automatically feed more ingredients into the crucible. Mine is running for several cycles doing alloying recipes.
I will replicate the setup some time™ using only GT6 and see how it behaves after i use it as i would in my normal world. All i know is, the molds stop responding to redstone going high after a while and instead only pours every 2.5 seconds. Once they have started pouring, they will keep pouring on inventory change though.