With interoperability and integrated design comes the need to have very strict control of the keys to the kingdom. If attributes cannot be global things, like objects, schedules, etc.,then the project lead needs to be able to coordinate the work of everyone else.
This collaborative work may require some really odd ways of parceling out the work and without access to attribute index numbers, then the project coordinator's task becomes monumental.
This argument applies to every enterprise who sets out to create a template, be they Joe the Plumber working in the basement of one of John McCain's houses, or the senior BIM coordinator at HOK.
An ArchiCAD template consists of much more than a PLN file, but the PLN file is becoming its weakest link.
Who wants to spend all their time administrating layer managment tasks?
If we don't we're just paying lip service to interoperablilty - talking the talk and not walking the walk.
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