[Schematron] Question about let-Element and multiply defined variables

Hi all,

Section 5.4.5 of Schematron 2016 reads:

,----
| 5.4.5 let element
|
| ...
|
| It is an error to reference a variable that has not been defined in
| the current schema, phase, pattern, or rule, if the query language
| binding allows this to be determined reliably. It is an error for a
| variable to be multiply defined in the current schema, phase, pattern
| and rule.
`----

I understand the last sentence "multply defined in the current schema,
phase, pattern and rule" to mean that I can define a variable in the
schema and then `redefine' the variable in a rule.

I.e. the following Schematron is *not* an error:

<schema xmlns="http://purl.oclc.org/dsdl/schematron">
  <let name="foo" value="'bar'"/
  <pattern>
    <rule context="/">
      <let name="foo" value="'baz'"/>
    </rule>
  </pattern>
</schema>

Is this the right interpretation?

Best,
  -- David

-- 
David Maus M.A.

Www: http://dmaus.name
Twitter: @_dmaus