Apparently, its not the UserLand Radio's code that is preserving the extra space.  Its Microsoft's HTML editor control used by UserLand Radio.  Oops.  I still love it and think more web sites and tools should do the same.  It makes text so much more readable.  Unfortunately, not everyone agrees.  Practically every site I visit uses only one space to separate sentences.  I suspect this is one of the reasons why studies have showed that long paragraphs tend to make eyes wander after a sentence or two.