We currently have only CAD in Windchill, no WTParts. Using only Promotion Requests, no change objects (yep, super crude compared to what we had at Alcon, but making progress).
Question: Can we apply a simple business rule to promotion somehow that checks if all first level child objects are at an appropriate state? I've never played with Business Rules yet - seems very powerful and worth learning. Jeff Z, hello if you're listening.
Short answer, yes you can add Business Rules to your promotion request workflow and the OOTB BOM Release Rule sounds like it would be what you need, however at least for us at Steelcase it is far from a "simple" rule. Out of the 20-30 business rules we have (most of which are custom code), the BOM Release Rule seems to give us the most trouble, however it is probably due to some self inflicted complexity since we have to deal with equivalent parts, etc.
Where are you looking to start? There is quite a bit of documentation on Business Rules, but it's always nice to have a high level rather than follow the spaghetti that is Windchill documentation.