Thanks for your reply Robert.
I read your article about Memento with great interest. Our needs are
somewhat peculiar. We certainly don't have problems with annotating
portals like cnn's. Memento type archiving is definitely out of scope
for us for this phase of the project with all its TimeGate
functionality, though I can definitely see its worth, and I am
grateful to you for pointing it out.
It does seem that OAC does not really cater for intended recipients
known from the outset and managing workflows between them. We intend
to provide an ecosystem for student to teacher collaboration where we
control content, storage, and the tools for annotations. It does look
like we will have to add perhaps our own namespaced extensions to the
standard to facilitate what we need.