Consider removing @startTime and @endTime in favor of relationships

[kvanmalssen]

The PBCore data model makes the use of expressing @startTime and @endTime potentially confusing. If these attributes are used with Intellectual Content items such as pbcoreDescription and the asset has multiple associated instantiations, and these don't have identical start times or durations, to which instantiation does the @startTime and @endTime apply?

This is a complex topic and touches on several others that have been raised as issues here, including questions around relationships and parts. However, for this particular point, I would be in favor of improving the documentation of expressing segments descriptions through the use of relationships and potentially parts, with @startTime and @endTime applied at the instantiation level as needed (e.g. <pbcoreInstantiation startTime='00:01:01'/> rather than enabling multiple, potentially conflicting options to do this at the Intellectual Content level.

[kvanmalssen]

Closing this issue. Going to reformulate. Sorry.