↓このスレッド、 SE-0110 以前（引数とタプルの区別）からひっくり返そうって言ってる・・・。 https://lists.swift.org/pipermail/swift-evolution/Week-of-Mon-20170605/037054.html
As one of many who is directly affected and wants resolution, I think the discussion of re-evaluating SE-0110 most certainly expands to these earlier decisions. While Swift has moved in the direction of distinguishing tuples and argument lists in decidedly different ways, I think it's perfectly valid to consider the alternative: a simpler and equally-valid solution: flattened tuples that are isomorphic to argument lists.