Having met and known Matt for like nine or so years, it's my personal feeling that he doesn't do this for the purpose of controlling or communicating a message. He does it from a genuine desire to be helpful to web publishers. His outreach began as posting on WebmasterWorld to help webmasters and the way he communicated grew from there but the focus, in my opinion, has always been on helping web publishers understand what are Google friendly activities publishers should be pursuing and to clarify for others what is not Google friendly and likely to hurt those publishers. Aside from his duties at Google, helping web publishers is what his volunteer role on WebmasterWorld originally was and from what I can see what his "volunteer" role continues to be. That's not speculation, that's my personal observations of him in person on dozens of occasions.
Too much emphasis on Matt
There is a blogging culture that for attention-getting purposes focus on sowing dread based on whatever Matt happens to say. They treat his words as if he is privy to all parts of the planning and execution of all the different parts of what you see after you hit the submit button. He's not. Personally I think many in the industry, being new to the industry and not knowing Matt's history, assume his role in the algo is larger than it really is. At least their behavior indicates that they assign too much importance to what he says.
The bottom line is that Matt is a person of good character who helps web publishers because deep down he is a good and decent person. That is pretty much what Matt Cutts is about.