Weird behavior w/Angel's refining

[Cagbee]

I'm noticing some weirdness regarding Angles refining and was wondering if anyone else noticed it too. I noticed thats with T1 sort my inserters ALWAYS put copper on one side of the belt and the slag on the other side and iron is more or less even. The iron makes sense since I do have two inserters pulling out of the sorter at all times and it depends on what order they take them from the sorter. But id figure its random which inserter takes from what slot. Screen shot provided.