How about kicking around a few example sentences?  Mayhaps we'll get a
debate started, the entire thread of which you might publish in
"Syntax."  For example, I wonder whether the subordinating particle and
the placement of the clause will have something to do with its emphasis
as main or secondary idea.  A "because" clause placed initially, seems to
carry much emphasis; a, say, "when" clause placed at the end of a
sentence seems to carry secondary emphasis.
 
==Cheerio, Reinhold
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                         Dr. Reinhold Schlieper
Humanities Department                              500 Shadow Lakes Boulevard
Embry-Riddle Aeronautical University                            Apartment 139
Daytona Beach FL  32114                                Ormond Beach FL  32174
Phone: 904-226-6664                                       Phone: 904-676-9392
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