The main problem this framework has isn't its reference-style documentation (if a framework looks good enough I'm willing to do some extra work figuring out how to use it). Kendo's real problem is its licence. Apart from seeing how "awesome" it is you can't do shit with it.
Here's the licence: http://gd.is/qDdw
Q: How is Kendo UI licensed? Is it open source?
Kendo UI is dual-licensed, Commercial and Open Source (GPLv3).
The Commercial license includes full source, professional support, access to the latest Kendo UI hotfix builds, and priority influence on the Kendo UI roadmap. During the Beta phase, the framework is licensed under a Beta license and no commercial license is available.
snippet below:
1. Grant. Telerik hereby grants to you, and you accept, a non–exclusive, non–transferable license to install and use the Software for evaluation purposes only, solely as authorized below. ....