Adding since-version tags to the docs?

Hello,

I often find it pity that our docs are missing any information on since
when a certain GUC setting, SQL-level command or function was introduced.

Clicking through the "this page in other versions" links at the top of a
webpage does help, but you still need to do some guessing (binary search?)
with the clicks. :-)

It would be nice if we could make a script that would parse the sgml files
and for every symbol it finds it would add a tag like "Since version 9.x".
Such a script could start by checking out REL9_0_STABLE and looking through
all symbols it can find, tagging them "Since 9.0". Then it could commit
the result, check out the next version branch and apply said commit (some
manual effort to merge it might be required), and repeat the process,
assuming all newly found symbols must be introduced in this new version.

That is for the lists, tabular representation might require adding a new
column, I'm not sure what would be the best format.

After this process is done once, we can have a requirement that every newly
introduced symbol/command be tagged manually by the patch author.

Do you think such approach will work? Is there interest in having this
done?

--
Alex