what does the current "splitter" do... actually: it "branches", e: or "mixes"
a splitter would be more like this?

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this leads to the following:
removing the ability of underground-belts to actually split or more precisely: prevent one half of the belt from working...
--- which i personally would consider as unlogical or unintuitive behaviour... why? because when you have items on a conveyer belt
------- there is no way to actually stop one half of working... ofcourse this is currently not completely avoidable, because of taking from a full belt etc...
well anyways
