In addition to out discussion in the meeting on May 7, the reason I think why we should remove "Change" from our domain model is as follows.
In the model of our base document, a Change represents a relation between superseded and superseding ManagedItems.
But in our scenarios, most typical changes of ManagedItems are changes of their properties, not replacements by another ManagedItems.
Changes of ManagedItems should be managed by versions of each item and configurations of them which is the way we expect the CCM Specification will provide.
(This issue may be closed now.)
References:
Tracked Resource Set (TRS) specification: http://open-services.net/wiki/core/TrackedResourceSet-2.0/
OASIS OSLC Configuration Management TC: https://wiki.oasis-open.org/oslc-ccm/