It's certainly possible with the API...
Mike, I think I'm working on the same thing and have the same setup as you so far. That is, an ECN card with change info on tab one linked to an MS Office form.
I'll also use Paste as Reference. I'm not really seeking to list those affected documents in the ECO card, though. They are already just one click away on the Bill of Materials tab for the change document. Like you, I'm not interested in having it copied or retyped to the card from another source, and the BOM tab should display a pretty complete list of the affected item properties we need.
On the other hand, what I do want is to display that same BOM on the ECN document itself. I want to be able to associate change-type (fix, release, improvement, etc.) information and "from-to" revision info with each item (it doesn't have to be linked). In our case, the change form (not the data card) has to be preserved as a complete record of the change.
I hope that helps you out a little, and maybe you or someone else has a tip for getting BOM into the Office document?