<select1/> and <setvalue/>

A simple <select/> (i.e. one with <value/> children), essentially uses 
concat() and <setvalue/> to set the @ref
A complex <select/> (i.e. with <copy/> children), uses <insert/> and 
<delete/>.

A simple <select1/> just uses <setvalue/>, but a complex <select1/> has a 
semantic that you might be able to replicate with a <delete/> followed by 
an <insert/>, but is essentially a semantic that a user can't replicate 
with an atomic action.

Should there be a <setcopy/> (or similar)? Or have I missed something?

Steven