It works in binding scenarios. But there should be groups, in order to break their content in multiple lines.
When Simple Binding is used, there are no groups (see Nodes and Items), therefore GroupColumnCount can't be used.
If a Node has only one GroupItem (this is the case in Simple Binding), this single item is all the content of a single group.
I hope this explains it better.
Having the ability to make the OrgChart's presentation more compact in Simple Binding scenarios is something that we are currently thinking about.
the Telerik team
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