As mentioned before with the current version, the "hack" demonstrated in the blogpost is the only possible approach towards the problem. Since we are working on an integrated feature in RadGridView to support multiple column headers, it would be hard to invest in supporting and fixing/improving the sample from the blog post as well.
In other words - there will be a full support for frozen columns, grouping , sorting etc. once we have this one as an offical feature integrated in RadGridView.
the Telerik team
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