On how Titicut Follies and Salesman differ we can say any number of things. But I guess that the mix between their differences and similarities is what makes both films from that same period become interesting and pertaining to each other. As we watch both films we get a sense that the camera is just as a window that let's us see thru this transparent glass the world that surrounds us, unaltered. Only this is far from true, as both films have those same ideals even if they did not accomplish them to perfection. .
And where they failed in their own ideals is that both, Wiseman and the Maysles brothers, did affect the scene by bringing their cameras and sound recoding devises. What we see in the scenes of those films are people depicted as they were supposed to be in "real" life. We are brought upon this set of characters whose storyline we follow and get a sense of narrative. We see differences in the way some of the shots are made. We get alternate senses of space by the use of the zoom lens and framing of the action. .
But we get transported to the action in both films. The camera is there, on a "typical-everyday life" moments to capture the evolution of its participants. In both films we can see despair and disgruntlement by either loons or sales people. And in both films this is accomplished by the keen eye of the cameraman who is able to capture body language and follow the action in a very new way, as equipment had just turned "portable" and they could lip-sync audio as well as take the cameras and follow their subjects with fair ease and agility. New kinds of takes were being produced on the fly, as now they could dolly and pan and zoom, which enriched the visual sequence in a great manner. .
I think that both films are completely successful in portraying human emotion and responses to different situations; although at times we can see the influence of the camera on the way the subjects talk or react.