It doesn't print 2 header.php's, it does print 2 sets of:
<html> <head> blah </head> <body>
Wouldn't it be better for this modification to add the correct threads code into the current photopost code instead of choosing between the 2 or using both? The instructions are already having us replace that exact code in pp-inc.php. Maybe commenting out the send_header line or something would come close to fixing it.
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