If ID is provided in add(), sync does not update _pristineData and Create/Update are not invoked.

Hello again Andy,

The update method will not be called because the record is not modified.
Regarding your suggestions:

1. The current logic is to check for the ID field value and is described in the documentation. If you believe that it should be changed then I can suggest to open a request in our user voice forum.
2. The pristine data should be updated only when the records are synchronized with the server. Otherwise, it will not be correct if the server is not able to save the changes and returns an error response.
3. This will be a breaking change and will prevent adding records in all cases that do not require synchronizing or cancelling the changes via the dataSource.

Regards,
Daniel
Telerik