The mistake the Liberals have made is their wording in explaining this tax change.  
My deceased husband was a Specialist physician.  Every year his partnership's accountants assigned thousands of dollars to family members who did nothing.  He paid much less       income tax than I did, even though I made less than a third of what he did. 
Reports I cannot personally confirm from friends suggest similar tactics by legal partnerships.
Morneau needed to say this "situation" will not be able to avoid taxation without identifying any professions or company types; and identify "situations" that are not, by any criteria, (eg. family farms or small businesses that do not even have income to shift/hide) avoiding their legitimate tax obligations.   Things have become unacceptably personal because of this failure in presentation.    A skilled communicator could still fix it (in my opinion).