I was wondering if somebody could provide an example where using

mode="#all"

(http://www.w3.org/TR/xslt20/#modes)

is necessary and useful.

It seems to me that using this feature can be dangerous and harmful --
when should we recommend it?

I use it to skip nodes.  Instead of
<xsl:template match="unwanted-node" mode="mode-1"/>
...
<xsl:template match="unwanted-node" mode="mode-n"/>

I just write
<xsl:template match="unwanted-node" mode="#all"/>

You could also use it to be sure to always process a certain node
(when the above XSLT templates have an actual body).

--
Cheers,
Dimitre Novatchev
---------------------------------------
Truly great madness cannot be achieved without significant intelligence.

Regards,
Rene
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