Alas, this admirably ambitious sentence falls just slightly short of grammatical correctness. If only the word "made" had been used instead of "allowed," the result would have been impeccable. English is so delicate, and so unforgiving. Tremendous movie, though. Masterpiece.
Ms Kazan is a painstaking artist. She cares about the fine details, because she knows, as Goethe knew, that God is in them. She herself notices and regrets her slips and errors, as must any aspirant to perfection. I'm just a sympathetic fellow struggler and sinner. I'm a fan.