[thwarted]

I am assuming that dealing with how and what proxies cache is a long standing potential issue that anything here does not change at all. A caching proxy could currently use a truncated path on a GET request to build a cache key and it would not be caching the correct data. Section 2.1 in its entirety, along with the defined meanings of MAY, MUST and SHOULD, tell caches how to operate. A caching proxy not caching and returning the right content because it does not take into account the necessary data when determining the cache key is broken, and semantic understanding of the request is a local concern so any non-local cache needs to acknowledge that it doesn't have semantic understanding and use the byte array that is the body as a input to determine a cache key.