Danny,

Static URLs are indexed much more quickly than dynamic URLs, if dynamic URLs get indexed at all (and no, not every engine indexes dynamic URLs).  Like you said previously, only a minute fraction of your old dynamic posts made it into Google.   

 So most are going from something like this: http://www.congenitaladrenalhyperplasia.org./forums/main/thread.php?threadid=12345&sort=date

to this:

http://www.congenitaladrenalhyperplasia.org./forums/main/thread.php

A search engine wants to only list pages in its index that are unique. Search engines combat this issue by cutting off the URLs after a specific number of variable strings (e.g.: ? & =) and dynamic and script posts often exceed this.  So my understanding is that you probably have a bunch of URLs like the one above and that is holding you back in the PageRank. 

So if you are rewriting the URLs and making each page unique html (maybe this is where we are talking about two different things?) and therefore more agreeable to a search engine, they’ll be indexed easier and faster.  Google will spider directly (if html) and perhaps frequently, and that will produce more posts as pages as search results.  This is how other forums with a bunch of activity display pages of post results after a Google keyword search.  I don’t see how you get around this in the longrun if you are doing the rewriting.     

Are you using some sort of "cloaking" type rewrite software that allows you to get around this and revert back to the dynamic and fool the search engines?  Otherwise, I don’t see how you boost your PageRank and get around not displaying more posts as search results.

Alison