RE: Draft finding - "Transitioning the Web to HTTPS"

> > ...  the text of the HTTP RFC provides strong support
> > for the idea that a transforming proxy is legitimate.  

"not disallowed" doesn't mean "legitimate"; legitimacy is primarily a social and not technical question.

For the IAB's reading of the role of transformational proxies in Internet (Web) Architecture, see 
https://tools.ietf.org/html/rfc3238

   This document includes comments and recommendations by the IAB on
   some architectural and policy issues related to the chartering of
   Open Pluggable Edge Services (OPES) in the IETF.  OPES are services
   that would be deployed at application-level intermediaries in the
   network, for example, at a web proxy cache between the origin server
   and the client.  These intermediaries would transform or filter
   content, with the explicit consent of either the content provider or
   the end user.



http://datatracker.ietf.org/wg/opes/charter/