>   On the other hand, maybe a way to tell the processor to 
> deactivate static error checks at one place (because we know 
> the generated code there is correct even if it can look 
> suspicious) would be interesting.

This is what "treat as" is designed for. I think that even completely crazy
things like

<xsl:apply-templates select="23 treat as node()"/>

should result in run-time rather than compile-time errors. (But I wouldn't
swear that it always works.)

Michael Kay
http://www.saxonica.com/