For the record, we do say that @value gets converted to a string (in the 
meeting I said we say it somewhere, but I couldn;t remember where). It's 
here: 
https://www.w3.org/community/xformsusers/wiki/XForms_2.0#The_value_and_mediatype_Attributes
4.3 The value and mediatype Attributes[edit]
The value attribute is used by elements to evaluate an expression; some 
elements that carry it also carry the mediatype attribute that indicates 
how to interpret the resulting value.
value
An expression. If the result is to be used as a string, then the result of 
the expression is processed as if by a call to the string conversion 
function as described in the expression module; an empty string is used if 
the evaluation fails. If the element has PCDATA content, then the result of 
the expression overrides that content.
On Friday 14 January 2022 16:17:13 (+01:00), XForms Users Community Group 
Issue Tracker wrote:
 > ACTION-2312: Devise text for submission using @value
 >
 > https://www.w3.org/2005/06/tracker/xforms/actions/2312
 >
 > Assigned to: Steven Pemberton
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