One disadvantage of the proposed idea is that it will not cache very nicely at the HTTP level, ie. GETs that you would normally offload to a CDN. Although it w

One disadvantage of the proposed idea is that it will not cache very nicely at the HTTP level, ie. GETs that you would normally offload to a CDN. Although it would be technically possible, I am not aware of any CDN that lets you cache based on the content of a multipart form.