question/comment on draft-ietf-httpbis-p5-range-20.txt

Hi all.
I originally posted the question below to the authors of the range-related ID, but they suggested I post to the entire list.  I just joined and am now doing so.  Please see the questions below.

To provide a bit more background, these questions are coming up in the context of MPEG-DASH, where (potentially real-time generated) media segments are being fetched by a client via HTTP, possibly with Range requests.  As a possible alternative to what I mentioned below in the second half, would it be possible to clarify the use of "Range: 0-" as a request for 'whatever you have available for me right now'.

Thanks,
- Kevin

From: <Fall>, Kevin Fall <kfall@qualcomm.com<mailto:kfall@qualcomm.com>>
Date: Wednesday, September 12, 2012 3:51 AM PDT
To: "fielding@gbiv.com<mailto:fielding@gbiv.com>" <fielding@gbiv.com<mailto:fielding@gbiv.com>>, "ylafon@w3.org<mailto:ylafon@w3.org>" <ylafon@w3.org<mailto:ylafon@w3.org>>, "julian.reschke@greenbytes.de<mailto:julian.reschke@greenbytes.de>" <julian.reschke@greenbytes.de<mailto:julian.reschke@greenbytes.de>>
Subject: question/comment on draft-ietf-httpbis-p5-range-20.txt

Hi folks-

I was just reading over draft-ietf-httpbis-p5-range-20 and have two small comments/questions.
First, I see there are no examples where the multipart/byteranges response contains multiple ranges that are out of order.
As far as I can tell this is ok, but not explicitly mentioned or provided in an example.  If, indeed, this is ok, I believe it would be helpful to mention or illustrate.

Perhaps more controversial, Section 3.1 requires a Partial Content request to only be permitted if the corresponding request had a Range header field.
We at least have one case where it would be rather useful to allow a Partial Content / Content-Range response even if the request didn't include the Range header.
Would it be possible to consider replacing MUST with SHOULD in line #2 of Section 3.1? (along with maybe replacing 'partial GET' with simply 'GET' in line #1)?
[or similar wording such as Content-Range responses SHOULD only be present in responses if partial GETs were the request types].  I can explain the use case
in more detail if interested.

Thanks,
- Kevin