[HTML5 Ruby] Should we disallow <rp> appeared between <rt>?

Dear HTML5 editors,

In HTML5 CR document, the context of an <rp> element is described as
"As a child of a ruby element, either immediately before or
immediately after an rt or rtc element." [1].

As of it, it seems as if <rp> can appear between <rt> elements,
for example, as "<rt>A</rt><rp>B</rp><rt>A</rt>".

However, practically, such a thing wouldn't happen, and in the
segmentation and categorisation algorithm [2], pairing would be
inconsistent and may fail in such a case.

For example:

<ruby>b1<rb>b2</rb><rb>b3</rb><rt>t1</rt><rp>(</rp><rt>t2</rt></ruby>

will be paired to (b1,t1), (b2+b3,t2), but

<ruby>b1<rb>b2</rb><rb>b3</rb><rtc><rt>t1</rt><rp>(</rp><rt>t2</rt></rtc></ruby>

will be paired to (b1,t1) (b2,rp) (b3,t2).

Should we explicitly prohibit for <rp> to appear between <rt> elements
to prevent such a situation?

Any comment is appreciated.

Regards,

[1] ...
http://www.w3.org/html/wg/drafts/html/CR/text-level-semantics.html#the-rp-element
[2] ...
http://www.w3.org/TR/html5/text-level-semantics.html#segmentation-and-categorisation-of-ruby


-- 
---------------------------------------------------------------------
KAWABATA, Taichi E-mail: kawabata.taichi@gmail.com