Note: There has been no answer to Russ Housley's Gen-ART review comments yet.

- I suspect the term "confidential" as used here will turn out
to mislead or confuse some folks. The meaning is clear if one
reads the draft, but of course many people will just read some
stackexchange answer. It's probably too late to try change
that unless someone has a good term beginning with "c" to use
for c-werbrtc. The potential for confusion I think will be
that the other label might be assumed to not use a good
confidentiality mechanism on the wire, so folks might get
concerned that e.g. their DataChannel stuff can be read by a
middlebox.  (I just mention this in case the concern is
either new or has been bubbling up in the WG, feel entirely
free to ignore me if you want.)

- I forget how the screen sharing issue for WebRTC was
resolved. In any case, do the handling of screen sharing and
c-webrtc interact? Do you need to explain that there's some
non-browser "access" (origination really) of media on the
screen-sharer's machine?

- "clever arrangement of mirrors" - that is a nice way to
explain the futility of DRM :-)

Please excuse my ignorance (pointers would be appreciated, if this is explained elsewhere): do RTP intermediary need to be updated to understand this spec?
If yes, how can you enforce requirements on "c-webrtc"?

I agree with Stephen's comments on the word confidentiality, but can't think of an alternate word.  I think text describing how this is limited would be helpful in the introduction.  The clearest (at least to me) description of what is meant by confidentiality doesn't appear until the security considerations section.