Am I right in the assumption that this example is highly hypothetical?
Why would the code need to be able to deal with a case like this:
/bla/forum/12345?forum_id=67890
when all requests of the new form will be like this:
/bla/forum/12345
and all references in the (to avoid) old style like this:
/bla/forum-view?forum_id=12345
Thanks for the note on [ad_conn path_info] - that's right. I'd propably still use it rather than [ad_conn urlv] and treat it with [file split] before because it'll be easier to read when including the message_id, like /bla/forum/12345/54321, but maybe that's just meaningless personal preference.