Sorry, but your premise is wrong. There is information on the senator here........
http://www.ksfy.com/Stories/Story.cfm?SID=9422
and here........from Dec. 30th
A spokeswoman for the South Dakota Democrat, who turned 60 today, says Johnson is responsive to directions from his wife but has not yet spoken. She says it's too early to tell how long recovery will take.
Johnson's doctors say he remains in intensive care. His overall condition is said to have improved. Johnson is being weaned off sedation to help his brain heal from the surgery which was done to stop bleeding
So you have information both from his doctors and his office saying he is still in intensive care, weak on the left side, responsive to his wife, but has not yet spoken a word. This is what the doctor in the article was referencing when he gave his EDUCATED prognosis based on the information the PUBLIC has from the SENATOR'S OFFICE which quotes his WIFE, and what the hospital has released which quotes HIS DOCTORS.