>But this gives the next problem that if the input already has b/c it also
>will be transformed to <d />.

One mans problem is another mans solution ;-)
In one of my applications this is precisely the behaviour I want.

> This
>I solved by using mode="tree" in the <xml:apply templates select="$tree" />
>and the
><xsl:templates match="b/c">.

Yes, that is what I would do.  This means that you can decide on a
case by case basis whether given templates may be composed or not.  I
did not follow your proposal exactly, but I suspect it did not offer
this choice?

>It works, but I'm not really charmed about the solution. I also read
>something in the XSLT1.1 spec that the result tree fragments were going to
>be removed ? But I'm not sure (I'm not getting any response from
>w3c.org so I can't look it up). If they remove this feature, I hope they
>will add a slightly more elegant way to apply templates to result tree
>fragment.

They have not removed them exactly, they just removed the distinction
between RTF and node-set.  This allows the pattern I described: before
you would have had to use an extension function such as

 <xsl:apply-templates select="saxon:node-set($tree)"/>

Regards,
Trevor Nash

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