some comments/questions on ATAG2.0 SCs B.1.2.2 and B.1.2.3

B.1.2.2 - What is "optimizing web content transformations" - I notice a definition for "content transformations"
with a subcategory of "optimized", but just gives some examples of optimizing - do we need a further clarification/extension
to include all possible actions that might be considered optimizing as opposed to those that aren't?  How much optimization
would an optimizing transformation need to do to qualify under the premise of this SC?
accessibility information (WCAG) - is there going to be a committee set up to further examine the ATAG-WCAG relationship?
"input" - to the transformation (implied but does it need to be spelled out?  same for "output" - from the transformation?
What specifically does "preserved" mean in this context?  Is it just talking about just the form/syntax of the information
or the semantics as well?  Can we objectively measure "preservation"?  Is a transformation always from one web content
technology to another such technology?  What happens if the technology is "custom", proprietary, or "unknown"?

B.1.2.3 - refer to some B.1.2.2 comments - NOTE WCAG has an extra sentence in their "text alternative" definition
in latest editor's draft when compared to ATAG
definition - not sure if this is significant or not?  -
so if no text alternatives are in fact provided for non-text content even though they could be (possible to do so)
(and as maybe they should be for accessibility reasons?) does that mean that this SC is satisfied by default, or just
that this SC doesn't apply?  - please clarify..
Do we need a definition for "equivalent mechanism" or at least a clear understanding of what it specifically entails?
How would we (hopefully objectively) measure "equivalency" in this context?
What happens if the output doesn't satisfy our definition of "web content technology"?

Thanks and best wishes
Tim Boland NIST