Generally, masks are primarily worn by the user to minimize transmission of the virus. Which should be obvious that talking/coughing through a mask would decrease the amount of virus getting through to the environment.
On the other hand, masks offer very little protection by the user from getting the virus (last I looked at the data). Which again should be clear since if you walk through a viral environment, the virus could be picked up by your clothes, hands, face, eyes, etc, and even on your mask. Another reason why they strongly urge hand washing, so that you don't transmit the virus from your hands to your mouth, nose, etc.
TGibson (1/28/17); "..."a 4 or 5 on a scale of 1 to 10 for drama"...What's the worst? "...yelling matches with Thibs, everybody is just going crazy and I'm just sitting there...like, 'Don't call my name please..."