Yes, Casdon, I agree. There is so much media out there that it is remarkably easy to find ways to make people look good or bad, and making anyone seem dishonest is easy too. Shifting things out of context and juxtaposing them with clips made in a different context can easily show people as inconsistent, and that's without allowing for the fact that people often are. We all change our minds and get things wrong, and think again, particularly when being questioned about things we hadn't really considered. So long as the main policies remain solid, and we aren't being lied to deliberately it just stops debate when people squabble over tiny points and try to catch their rivals out.
Also, slightly tangentially, defining the boundaries of acceptability for belonging to a group then suggesting that anyone who thinks outside of that box is a traitor is manipulative (eg 'if you are a good socialist/feminist/Methodist/botanist you will know/think/want/believe the same as I do, and if not, you are wrong/misguided/duplicitous/treacherous, and not really a socialist/feminist/Methodist/botanist at all'). It's rarely done well, and when done clumsily people see straight through it and react against the attempt at manipulation.