We will remove the properties with our next release, however it's is essential to keep them obsolete in order to prevent any breaking changes by adopting our new version. I am sorry to hear that Blends reflection of our properties disregards the obsolete attribute. We will remove them in our next Q release just to make sure everybody has adopted the new ones.
Concerning the documentation, we are aware of this problem and we are currently working on uploading a newer version as soon as possible. Thank you for contacting us, and we look forward to receiving more valuable feedback from you.
the Telerik team