Maybe it has something to do with negative polarity, and the 'so'
construction being a post-noun modifier instead of a postverbal modifier,
as in the 'taller' case?
 
Johanna
 
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Johanna Rubba   Assistant Professor, Linguistics              ~
English Department, California Polytechnic State University   ~
San Luis Obispo, CA 93407                                     ~
Tel. (805)-756-2184  E-mail: [log in to unmask]      ~
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