No way to determine attachment creator via REST api

Not sure if this would be considered an improvement or a bug. When retrieving attachment info from the prototype rest api. (i.e. /rest/prototype/1/attachment), there isn't a field that indicates the user who uploaded the attachment. There is an "owner" field but this refers to the content the attachment is attached to. This seems like a major oversight since this field does exist in the old remote api (json-rpc, xml-rpc, soap).

You would probably say "oh, easy, just use the old remote api". The problem is that I have an attachment ID but the old api uses filename and page id to look up attachment. Therefore, to get the username of the attachment uploader, I need to currently make 2 requests. First, to the prototype api to get the information to make a request to the old remote api. Then to the old remote api.