Thank you for sharing your thoughts and insisting on adding such functionality.
We have thought over it once again and came to an idea for adding client functionality for add,remove Nodes and GroupItems in the future. A client-side event(like "nodeAdded" for example) will be fired in order to allow immediate update of the DataSource. Otherwise after a postback all the changes will be lost because RadOrgChart does not support automatic updates of the underlying DataSource.
I have created a PITS item where you can vote for this issue and follow its progress.
the Telerik team
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