Use and abuse of @summary

Hi Ian,
Ian hickson wrote:
"It is encouraging that certain users are in fact able to navigate the
Web without coming across the overwhelmingly bad uses of summary=""." [1]

"In fact, the main argument against keeping <table summary=""> is that
legacy content has abused it so badly that it is unusable. " [2]

Can you clarify what the basis for these claims of "overwhelmingly bad uses
of summary=""" are?

If they are based on the data gathered by Philip Taylor [3], he said
recently

"Philip notes that his thing was not attempting to be a particularly useful
or detailed or well-thought-out survey, it was just scraping some
easily-available information" [4]

Which suggests it is not a basis for claimimg that "legacy content has
abused it so badly that it is unusable" Likewise ben millards data [5] has
little to say about @summary use and nothing that supports such a claim.

On digging into philips data a little bit and measuring its effect upon
users who's screen reading software provides access to the information it is
found that in the overwhelming majority of cases the incorrect uses of
@summary are not announced to screan reader users. Why? Because screen
reading software (JAWS and Window eyes) that supports @summary also uses
heuristics to suppress the announcement of layout tables to users
Why? because of the rampant misuse of  tables for formatting content rather
than for organising data, as was intended. From adhoc testing I carried out
it appears that the presence or abscence of a @summary (whatever its
content) does not make a difference to whether a layout table is presented
to a user.

So i suggest from philips data, (informative as it may be, but a useful
basis for an objective assessment it is not), the net effect of the misuse
is minimal.

After last weeks html working group teleconference I undertook a small study
myself: summary attribute usage data (
http://www.paciellogroup.com/blog/misc/summary.html) I am not making any
wild claims about this study, but do suggest that from this sample, for the
large majority of cases where @summary was used, it was used on data tables
in way that may be useful to the users its intended for.

In conclusion: @summary is well supported by AT , its misuse at whatever
level (though I would say claims are overstated) has little effect upon
users.
Therefore I suggest that it would be useful to talk to the screen reader
users (its intended audience) that are on the W3C HTML working group and the
W3C WAI groups and heed their advice on the utility of the @summary.

[1] http://lists.w3.org/Archives/Public/public-html/2009Feb/0398.html
[2] http://lists.w3.org/Archives/Public/public-html/2009Feb/0393.html
[3] http://canvex.lazyilluminati.com/misc/summary.html
[4] http://krijnhoetmer.nl/irc-logs/html-wg/20090212#l-455
[5]  http://projectcerbera.com/web/study/2007/tables,
http://projectcerbera.com/web/study/2008/tables


-- 
with regards

Steve Faulkner
Technical Director - TPG Europe
Director - Web Accessibility Tools Consortium

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