Here’s a use-case: I would like to use OmniFocus as a unified task list for both my personal as well as my employment. However, due to security/privacy concerns, I’d like to sync the two pieces separately: The personal stuff to my own target (either Omni’s servers, or my own WebDAV), but the corporate stuff to a corporate server (presumably WebDAV).
You could use two different systems and use a Workflow to copy tasks from one to the other - if any crosstalk is needed.
More to the point, what would unification buy you?
I would get to use the same interface and application to manage all of my tasks in one place. A simple synchronization between the hypothetical two systems would result in the corporate events being copied out to a non-corporate system. (Similarly the personal data would be synced to the corporate system) Neither are desirable traits.
I’m also seeking this as the OmniSync servers are not allow to be used by my employer. Having a single view point, but implementing cross domain data flow controls with data separation, and multiple sync back ends for different “folders” or “identities” (think Apple Mail/Contacts/Calendars/Reminders/Notes managed by MDM where the user gets a single pane of glass view to inform decisions, but the data isn’t co-mingled on device, different accounts sync to different back ends, and managed data can be prevented from flowing into the unmanaged space by policy). Its fair enough for an employer to not want work tasks to end up on Omni’s servers, but its also fair for me to not sync my personal stuff to a WebDAV server inside the company (and need a VPN connection to access).