When designers copy, ummmm…I mean… draw inspiration from..yes, other designers, there is usually at least a few years in between when the original item/collection was shown and the reinterpretation. For F/W, Nicolas G. reinterpreted the Balenciaga archives from ’53-’57. In 2004, Tom Ford reinterpreted Yves’ 1977 Chinese collection for his fall YSL show. 
Credit: Style.com. Derek Lam & Chloé
Maybe due to the advent of high-speed Internet and Instant Messaging, but it seems that designer’s are not looking nearly as far back as they used to. I have already posted the numerous white, tent dresses that share a striking resemblance to Philo’s work at Chloé . Now, take a look at the shoes from Derek Lam’s S/S 2007 collection. Then, take a look at the shoes from Chloé’s F/W 2006 collection. Similarity much?
i agree with you totally on this issue. there are a lot of designers who seemingly are looking back for inspiration about as far as they can throw. a lot of the designers seem to have a bad case of chronic nostalgia.