What I meant was a bit different.

In the morph brush you have the option to use and combine existing morphs. So what you do is to make only the expressoion (and viseme morphs) and 3rd partyh morphs active. Then you use the morphbrush to change the expression directly on the face. 

So what you actually do is an alternative to using the dials. No new morphs are created.

It does show however that the default morphs (++ for V4) are pretty limited. If you would have more expression morphs, it would work better.
But it works on all figures (if they have existing expressions)