Should the client/server interface support the declaration of external variables?

Right now, consider an XQuery such as this one (simplified form shown)

declare variable $entry as xs:anyAtomicType external;

     <title>Copy of { $entry//atom:title/text() }</title>

Suppose "entry" is an element rendered into a blob of XML of 1000 characters and markup.  Before we can send above XQuery to the BaseX server, we have to replace all instances of '$entry' with the actual XML (as per the previous discussion that XQJ is deprecated and the client/server interface is the preferred way to communicate with BaseX).

This means that we're sending roughly 4x the amount of data (note that $entry is used four times above), just to be able to say "$entry//atom:title/text()". This can easily lead to unexpected performance as queries become more complicated; in addition and more importantly, it makes it really tough to debug the expanded XQuery if there is a need.

Why not extend the protocol so that a client can define the external variables in an XQuery first?

 - Godmar

ps: I understand that I could work around this by introducing additional variables with let, as in

let $dummy = $entry ...

and then using $dummy//atom:title/text() etc.  Awkward.