[TECH] Do we need gateway technique 3.1.2 Unambiguous decoding?

When I was compiling the end to end mapping for guideline 3.1 I found the 
following Gateway technique: 

3.1.2 Unambiguous decoding: 
Ensure that all characters and words in the content can be unambiguously 
decoded.
Editorial Note: This has been carried over from WCAG 1.0. I (Tom) am 
slightly unsure as to the meaning or need implied by this technique.
I'm not really sure what this means.  I did some searching in the mail 
archives and it seems related to what was previously checkpoint 1.5 back 
in June, 2002 (see  
http://lists.w3.org/Archives/Public/w3c-wai-gl/2002AprJun/0459.html for 
more details). 
And the August, 2002 working draft has the following:
<quote>
Checkpoint 1.5 Provide information needed for unambiguous decoding of the 
characters and words in the content.
Success criteria
You will have successfully met Checkpoint 1.5 at the Minimum Level if:
1.      text in the content is provided in Unicode or sufficient 
information is provided so that it will be automatically mapped back to 
Unicode.
You will have successfully met Checkpoint 1.5 at Level 2 if:
1.      passages or fragments of text occurring within the content that 
are written in a language other than the primary natural language of the 
content as a whole, are identified, including specification of the 
language of the passage or fragment.
2.      abbreviations and acronyms are clearly identified where they 
occur. (See also checkpoint 4.3.)
3.      symbols such as diacritic marks that are found in standard usage 
of the natural language of the content and necessary for unambiguous 
interpretation of words are present or another standard mechanism for 
disambiguation is provided.
You will have successfully met Checkpoint 1.5 at Level 3 if:
1.      the primary natural language of the content is identified at the 
page level.
</quote>
The success criteria above about the primary language must be specified, 
language phrases must be identified, and abbreviations and acronyms 
identified have become success criteria of Guideline 3.1.  I'm not sure 
what happened with diacritic marks. 
I believe that this Gateway technique needs more clarification or it 
should be removed.   If the above definition of unambiguous decoding is 
that the content has been provided in unicode or that character set has 
been identified, we should update the technique with that. But, that seems 
to have been since removed and rigthly so, in my opinion. 
The only other reference I could find in the mail archives was a 
discussion about controlled use of language (
http://lists.w3.org/Archives/Public/w3c-wai-gl/2002AprJun/0271.html) 
stared by Lisa Seeman back in May 2002.  But didn't clarify this much for 
me.
Have we covered unambiguous decoding with the language, acronym and 
abbreviation,  and other success criteria for guideline 3.1?   Can anyone 
shed any light on this technique or propose a rewrite? Or can it be 
removed?
thanks,
Becky Gibson
Web Accessibility Architect
                                                       
IBM Emerging Internet Technologies
5 Technology Park Drive
Westford, MA 01886
Voice: 978 399-6101; t/l 333-6101
Email: gibsonb@us.ibm.com