I've spent few minutes to create small control called RadPageStylist which will style all Telerik RadControls on desired page with desired Skin. The control is fairly simple - you have Skin property where you can set your skin and ApplySkin() method which can be executed for particular ASP.NET Control. The method is recursive and will locate all child ISkinableControls to set selected Skin.
Other possible approach is "Global skin setting for the entire web site/web application project" however in this case the skin registration is static.
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Vladimir Enchev is Director of Engineering, Native Mobile UI & Frameworks