You now can! We've just released a preview of Coherence Incubator 12.0.0 that is based on Coherence 12.1.2. This includes support for using the previous namespaces (like element:introduce-cache-config) with Coherence 12.1.2.
The 12.0.0-SNAPSHOT is now available on: https://maven.java.net/
The latest documentation for this SNAPSHOT is available here: http://coherence-community.github.io/coherence-incubator/12.0.0-SNAPSHOT/
We warmly welcome feedback for the new release!
Brian Oliver | Architect | Oracle Coherence