I actually disagree with your example. Taken ultra-literally, it could mean that 'I' was 'perched' and 'saw three black crows'. So I feel that 'crows black' was fine and French places adjectives after the word as standard. I have to rely on context to interpret the sentence, and that creates an iota of doubt which makes it read clumsily, or me read it clumsily. I think it's very nuanced and personal.