Your guess is right. The router has an undocumented pushState support implemented (you may check the source code for further details).
We decided to leave it like that mostly because pushState requires some non-trivial application architecture implementations – both client-side and server-side. Kendo UI being a client-side focused UI framework, we can't really offer a turnkey solution that matches the ease of usage our users have grown accustomed to with the rest of the framework - you can't really flip a flag and have your app work with pushState without reworking your server-side rendering logic - and the approach varies across different platforms.
Having said that, if you feel comfortable with the framework source code, you can always patch (or even monkey patch) the router settings if the pushState support is a requirement for your project. Yet, this mode is not something that we can officially support and provide assistance with.
the Telerik team
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