Vey good find, this formula. Unfortunately, not 100%. about a 2% margin in it.

I'm curious to know where it goes wrong. It's not in relation rounding. must be something to do with skills.

For example: Refining 123456 HDT and Liquizit to get Vitricyl.
With a refining skill of 3 and relation total of 13,71 in a lvl 1 refinery.

The formula says it should give 1030 of Vitricyl. The actual in-game number is 1049
Now, if I increase relation to a ridiculous number of relation, like 20, I get 1041. Still off and Obviously, I dont have that number of relation total. 

How did you come up with the Refinery number of 0,316?