The whole time Eliot was going over this issue last week I kept thinking “Why are we talking about pulling the reltables from the submaps ‘up into’ the root map?”
Yes, beginning with DITA 1.0 we thought that intermediate results of processing needed to be valid DITA, but we’ve moved away from that.
Perhaps for DITA 2.0 we need to get rid of verbiage such as “union of relationship tables,” and instead refer to something like “a union of the resolved links.”
We specify what we expect to be the final resolved links, and then let processors choose the methodology that they want to use.
Best, Kris Kristen James Eberlein Chair, OASIS DITA Technical Committee Owner, Eberlein Consulting LLC
Skype: kriseberlein; voice: +1 (919) 622-1501