Using before:|after:$phase on CLI does not work

If I try to use one of the new life cycle phase via command line like this:

mvn before:clean
...
[INFO] --------------------------------------------------------------------------------------------------------------------------
[ERROR] No plugin found for prefix 'before' in the current project and in the plugin groups [org.apache.maven.plugins, org.codehaus.mojo] available from the repositories [local (/Users/khm/.m2/repository), nexus (

That will fail (from my perspective as expected) because that's a conflict with the syntax for calling a goal of a plugin. That means at the moment it's not possible to call a thing like (before:|after:)$phase or alike...on command line...

This behaviour is already documented on https://cwiki.apache.org/confluence/display/MAVEN/Dynamic+phases 

The questions which arise:

• Should it be possible to call things like that via CLI? That could be helpful for testing things out?
• Or Should we at least correctly WARN about such situations? The above error message is from my point of view misleading..