Possible Ambiguity in Translation of Group Graph Patterns

Public SPARQL Dev mailing list,

In section 18.2.2.6 of the W3C Recommendation of SPARQL
1.1<http://www.w3.org/TR/sparql11-query/#sparqlTranslateGraphPatterns>,
there appears (to me) to be some ambiguity in the translation of group
graph patterns.  Specifically, in the pseudocode following "If the form is
GroupGraphPattern", the third (non-blank) line says "For each element E in
the GroupGraphPattern".  No order seems to be explicitly given (unless I
overlooked some mandate elsewhere in the recommendation), yet the order
seems to be significant since each iteration of the loop builds on the G
from the previous iteration.  Could someone please provide some clarity on
the matter or point out my misunderstanding?

Thank you.

-Jesse Weaver