I have already answered your support ticket with the same question and I am pasting my reply here for others that may have the same query:
The RadChart has similar functionality. It is described in the following help article: http://www.telerik.com/help/aspnet-ajax/chart-bar-overlap-percent-widht.html
For RadHtmlChart and KendoChart I cannot provide an estimate on such a feature, so what I can advise is monitoring the release notes after the respective releases to see when/if it becomes available.
the Telerik team
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