After days and days of combing SDN, SAP Notes and KBA's, StackOverflow and some questionable expert web sites, both before and after posting this question, I found a hint of a clue in Suresh Krishnamoorthy's response on Mar 14, 2007 to this thread: How to catch URL parameter from Portal URL in Web Dynpro iView which simply reminded the author to make sure his iView parameter Parameters to Pass from Page Request ( for URL Isolation) contained an asterisk "*".
Mine was blank.
This iView has been broken for months before it came to me for analysis. Nobody could figure out why it stopped working. We will probably never know if a value ever existed for that property.
Perhaps this is another scenario which demonstrates the need for Portal Developers to have at least Content Administration roles in the Enterprise Portal system they support, even if SOD forbids assignment of other administration roles such as System, User, and Super.